Primary ciliary dyskinesia-5 (CILD5) is an autosomal recessive disorder characterized by early onset of a progressive decline in lung function due to an inability to clear mucus and particles from the airways. Affected individuals have recurrent infections of the sinuses, ears, airways, and lungs. Sperm motility is also decreased. Individuals with CILD5 do not have situs inversus (summary by Olbrich et al., 2012). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia (PCD; CILD) is an autosomal recessive disorder resulting from loss of normal ciliary function. Kartagener (pronounced KART-agayner) syndrome is characterized by the combination of primary ciliary dyskinesia and situs inversus, and occurs in approximately half of patients with ciliary dyskinesia. Since normal nodal ciliary movement in the embryo is required for normal visceral asymmetry, absence of normal ciliary movement results in a lack of definitive patterning; thus, random chance alone appears to determine whether the viscera take up the normal or reversed left-right position during embryogenesis. This explains why approximately 50% of patients, even within the same family, have situs inversus (summary by Afzelius, 1976; El Zein et al., 2003). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia and the Kartagener syndrome, see CILD1 (244400).

Primary ciliary dyskinesia-2 (CILD2) is an autosomal recessive disorder arising from immotile cilia that lack both outer and inner dynein arms. Ineffective airway mucociliary clearance usually manifests within the first year of life with recurrent infections resulting in a chronic respiratory condition and progressing to permanent lung damage. Some patients have nasal polyps, infertility, or hearing loss. About half of patients have situs inversus (Mitchison et al., 2012). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

A rare, genetic, ectodermal dysplasia syndrome characterized by the association of hypohidrotic ectodermal dysplasia (manifesting with the triad of hypohidrosis, anodontia/hypodontia and hypotrichosis) with primary hypothyroidism and respiratory tract ciliary dyskinesia. Patients frequently present urticaria pigmentosa-like skin pigmentation, increased mast cells and melanin depositions in the dermis and severe, recurrent chest infections. There have been no further descriptions in the literature since 1986.

Rarely, individuals with primary ciliary dyskinesia have an accumulation of fluid in the brain (hydrocephalus), likely due to abnormal cilia in the brain.\n\nAnother feature of primary ciliary dyskinesia is recurrent ear infections (otitis media), especially in young children. Otitis media can lead to permanent hearing loss if untreated. The ear infections are likely related to abnormal cilia within the inner ear.\n\nPrimary ciliary dyskinesia can also lead to infertility. Vigorous movements of the flagella are necessary to propel the sperm cells forward to the female egg cell. Because their sperm do not move properly, males with primary ciliary dyskinesia are usually unable to father children. Infertility occurs in some affected females and is likely due to abnormal cilia in the fallopian tubes.\n\nApproximately 12 percent of people with primary ciliary dyskinesia have a condition known as heterotaxy syndrome or situs ambiguus, which is characterized by abnormalities of the heart, liver, intestines, or spleen. These organs may be structurally abnormal or improperly positioned. In addition, affected individuals may lack a spleen (asplenia) or have multiple spleens (polysplenia). Heterotaxy syndrome results from problems establishing the left and right sides of the body during embryonic development. The severity of heterotaxy varies widely among affected individuals.\n\nSome individuals with primary ciliary dyskinesia have abnormally placed organs within their chest and abdomen. These abnormalities arise early in embryonic development when the differences between the left and right sides of the body are established. About 50 percent of people with primary ciliary dyskinesia have a mirror-image reversal of their internal organs (situs inversus totalis). For example, in these individuals the heart is on the right side of the body instead of on the left. Situs inversus totalis does not cause any apparent health problems. When someone with primary ciliary dyskinesia has situs inversus totalis, they are often said to have Kartagener syndrome.\n\nIn the respiratory tract, cilia move back and forth in a coordinated way to move mucus towards the throat. This movement of mucus helps to eliminate fluid, bacteria, and particles from the lungs. Most babies with primary ciliary dyskinesia experience breathing problems at birth, which suggests that cilia play an important role in clearing fetal fluid from the lungs. Beginning in early childhood, affected individuals develop frequent respiratory tract infections. Without properly functioning cilia in the airway, bacteria remain in the respiratory tract and cause infection. People with primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections can result in a condition called bronchiectasis, which damages the passages, called bronchi, leading from the windpipe to the lungs and can cause life-threatening breathing problems.\n\nPrimary ciliary dyskinesia is a disorder characterized by chronic respiratory tract infections, abnormally positioned internal organs, and the inability to have children (infertility). The signs and symptoms of this condition are caused by abnormal cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. They are found in the linings of the airway, the reproductive system, and other organs and tissues. Flagella are tail-like structures, similar to cilia, that propel sperm cells forward.

Primary ciliary dyskinesia is a disorder characterized by chronic respiratory tract infections, abnormally positioned internal organs, and the inability to have children (infertility). The signs and symptoms of this condition are caused by abnormal cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. They are found in the linings of the airway, the reproductive system, and other organs and tissues. Flagella are tail-like structures, similar to cilia, that propel sperm cells forward.\n\nIn the respiratory tract, cilia move back and forth in a coordinated way to move mucus towards the throat. This movement of mucus helps to eliminate fluid, bacteria, and particles from the lungs. Most babies with primary ciliary dyskinesia experience breathing problems at birth, which suggests that cilia play an important role in clearing fetal fluid from the lungs. Beginning in early childhood, affected individuals develop frequent respiratory tract infections. Without properly functioning cilia in the airway, bacteria remain in the respiratory tract and cause infection. People with primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections can result in a condition called bronchiectasis, which damages the passages, called bronchi, leading from the windpipe to the lungs and can cause life-threatening breathing problems.\n\nSome individuals with primary ciliary dyskinesia have abnormally placed organs within their chest and abdomen. These abnormalities arise early in embryonic development when the differences between the left and right sides of the body are established. About 50 percent of people with primary ciliary dyskinesia have a mirror-image reversal of their internal organs (situs inversus totalis). For example, in these individuals the heart is on the right side of the body instead of on the left. Situs inversus totalis does not cause any apparent health problems. When someone with primary ciliary dyskinesia has situs inversus totalis, they are often said to have Kartagener syndrome.\n\nApproximately 12 percent of people with primary ciliary dyskinesia have a condition known as heterotaxy syndrome or situs ambiguus, which is characterized by abnormalities of the heart, liver, intestines, or spleen. These organs may be structurally abnormal or improperly positioned. In addition, affected individuals may lack a spleen (asplenia) or have multiple spleens (polysplenia). Heterotaxy syndrome results from problems establishing the left and right sides of the body during embryonic development. The severity of heterotaxy varies widely among affected individuals.\n\nPrimary ciliary dyskinesia can also lead to infertility. Vigorous movements of the flagella are necessary to propel the sperm cells forward to the female egg cell. Because their sperm do not move properly, males with primary ciliary dyskinesia are usually unable to father children. Infertility occurs in some affected females and is likely due to abnormal cilia in the fallopian tubes.\n\nAnother feature of primary ciliary dyskinesia is recurrent ear infections (otitis media), especially in young children. Otitis media can lead to permanent hearing loss if untreated. The ear infections are likely related to abnormal cilia within the inner ear.\n\nRarely, individuals with primary ciliary dyskinesia have an accumulation of fluid in the brain (hydrocephalus), likely due to abnormal cilia in the brain.

Rarely, individuals with primary ciliary dyskinesia have an accumulation of fluid in the brain (hydrocephalus), likely due to abnormal cilia in the brain.\n\nAnother feature of primary ciliary dyskinesia is recurrent ear infections (otitis media), especially in young children. Otitis media can lead to permanent hearing loss if untreated. The ear infections are likely related to abnormal cilia within the inner ear.\n\nPrimary ciliary dyskinesia can also lead to infertility. Vigorous movements of the flagella are necessary to propel the sperm cells forward to the female egg cell. Because their sperm do not move properly, males with primary ciliary dyskinesia are usually unable to father children. Infertility occurs in some affected females and is likely due to abnormal cilia in the fallopian tubes.\n\nApproximately 12 percent of people with primary ciliary dyskinesia have a condition known as heterotaxy syndrome or situs ambiguus, which is characterized by abnormalities of the heart, liver, intestines, or spleen. These organs may be structurally abnormal or improperly positioned. In addition, affected individuals may lack a spleen (asplenia) or have multiple spleens (polysplenia). Heterotaxy syndrome results from problems establishing the left and right sides of the body during embryonic development. The severity of heterotaxy varies widely among affected individuals.\n\nSome individuals with primary ciliary dyskinesia have abnormally placed organs within their chest and abdomen. These abnormalities arise early in embryonic development when the differences between the left and right sides of the body are established. About 50 percent of people with primary ciliary dyskinesia have a mirror-image reversal of their internal organs (situs inversus totalis). For example, in these individuals the heart is on the right side of the body instead of on the left. Situs inversus totalis does not cause any apparent health problems. When someone with primary ciliary dyskinesia has situs inversus totalis, they are often said to have Kartagener syndrome.\n\nIn the respiratory tract, cilia move back and forth in a coordinated way to move mucus towards the throat. This movement of mucus helps to eliminate fluid, bacteria, and particles from the lungs. Most babies with primary ciliary dyskinesia experience breathing problems at birth, which suggests that cilia play an important role in clearing fetal fluid from the lungs. Beginning in early childhood, affected individuals develop frequent respiratory tract infections. Without properly functioning cilia in the airway, bacteria remain in the respiratory tract and cause infection. People with primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections can result in a condition called bronchiectasis, which damages the passages, called bronchi, leading from the windpipe to the lungs and can cause life-threatening breathing problems.\n\nPrimary ciliary dyskinesia is a disorder characterized by chronic respiratory tract infections, abnormally positioned internal organs, and the inability to have children (infertility). The signs and symptoms of this condition are caused by abnormal cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. They are found in the linings of the airway, the reproductive system, and other organs and tissues. Flagella are tail-like structures, similar to cilia, that propel sperm cells forward.

Primary ciliary dyskinesia is a disorder characterized by chronic respiratory tract infections, abnormally positioned internal organs, and the inability to have children (infertility). The signs and symptoms of this condition are caused by abnormal cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. They are found in the linings of the airway, the reproductive system, and other organs and tissues. Flagella are tail-like structures, similar to cilia, that propel sperm cells forward.\n\nIn the respiratory tract, cilia move back and forth in a coordinated way to move mucus towards the throat. This movement of mucus helps to eliminate fluid, bacteria, and particles from the lungs. Most babies with primary ciliary dyskinesia experience breathing problems at birth, which suggests that cilia play an important role in clearing fetal fluid from the lungs. Beginning in early childhood, affected individuals develop frequent respiratory tract infections. Without properly functioning cilia in the airway, bacteria remain in the respiratory tract and cause infection. People with primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections can result in a condition called bronchiectasis, which damages the passages, called bronchi, leading from the windpipe to the lungs and can cause life-threatening breathing problems.\n\nSome individuals with primary ciliary dyskinesia have abnormally placed organs within their chest and abdomen. These abnormalities arise early in embryonic development when the differences between the left and right sides of the body are established. About 50 percent of people with primary ciliary dyskinesia have a mirror-image reversal of their internal organs (situs inversus totalis). For example, in these individuals the heart is on the right side of the body instead of on the left. Situs inversus totalis does not cause any apparent health problems. When someone with primary ciliary dyskinesia has situs inversus totalis, they are often said to have Kartagener syndrome.\n\nApproximately 12 percent of people with primary ciliary dyskinesia have a condition known as heterotaxy syndrome or situs ambiguus, which is characterized by abnormalities of the heart, liver, intestines, or spleen. These organs may be structurally abnormal or improperly positioned. In addition, affected individuals may lack a spleen (asplenia) or have multiple spleens (polysplenia). Heterotaxy syndrome results from problems establishing the left and right sides of the body during embryonic development. The severity of heterotaxy varies widely among affected individuals.\n\nPrimary ciliary dyskinesia can also lead to infertility. Vigorous movements of the flagella are necessary to propel the sperm cells forward to the female egg cell. Because their sperm do not move properly, males with primary ciliary dyskinesia are usually unable to father children. Infertility occurs in some affected females and is likely due to abnormal cilia in the fallopian tubes.\n\nAnother feature of primary ciliary dyskinesia is recurrent ear infections (otitis media), especially in young children. Otitis media can lead to permanent hearing loss if untreated. The ear infections are likely related to abnormal cilia within the inner ear.\n\nRarely, individuals with primary ciliary dyskinesia have an accumulation of fluid in the brain (hydrocephalus), likely due to abnormal cilia in the brain.

Primary ciliary dyskinesia is an autosomal recessive disorder resulting from loss of normal ciliary function. Kartagener (pronounced KART-agayner) syndrome is characterized by the combination of primary ciliary dyskinesia and situs inversus, and occurs in approximately half of patients with ciliary dyskinesia. Since normal nodal ciliary movement in the embryo is required for normal visceral asymmetry, absence of normal ciliary movement results in a lack of definitive patterning; thus, random chance alone appears to determine whether the viscera take up the normal or reversed left-right position during embryogenesis. This explains why approximately 50% of patients, even within the same family, have situs inversus (Afzelius, 1976; El Zein et al., 2003). For a general description and a discussion of genetic heterogeneity of primary ciliary dyskinesia and Kartagener syndrome, see CILD1 (244400).

Primary ciliary dyskinesia is an autosomal recessive disorder resulting from loss of normal ciliary function. Kartagener (pronounced KART-agayner) syndrome is characterized by the combination of primary ciliary dyskinesia and situs inversus, and occurs in approximately half of patients with ciliary dyskinesia. Since normal nodal ciliary movement in the embryo is required for normal visceral asymmetry, absence of normal ciliary movement results in a lack of definitive patterning; thus, random chance alone appears to determine whether the viscera take up the normal or reversed left-right position during embryogenesis. This explains why approximately 50% of patients, even within the same family, have situs inversus (Afzelius, 1976; El Zein et al., 2003). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia and the Kartagener syndrome, see CILD1 (244400).

Primary ciliary dyskinesia is a disorder characterized by chronic respiratory tract infections, abnormally positioned internal organs, and the inability to have children (infertility). The signs and symptoms of this condition are caused by abnormal cilia and flagella. Cilia are microscopic, finger-like projections that stick out from the surface of cells. They are found in the linings of the airway, the reproductive system, and other organs and tissues. Flagella are tail-like structures, similar to cilia, that propel sperm cells forward.\n\nSome individuals with primary ciliary dyskinesia have abnormally placed organs within their chest and abdomen. These abnormalities arise early in embryonic development when the differences between the left and right sides of the body are established. About 50 percent of people with primary ciliary dyskinesia have a mirror-image reversal of their internal organs (situs inversus totalis). For example, in these individuals the heart is on the right side of the body instead of on the left. Situs inversus totalis does not cause any apparent health problems. When someone with primary ciliary dyskinesia has situs inversus totalis, they are often said to have Kartagener syndrome.\n\nApproximately 12 percent of people with primary ciliary dyskinesia have a condition known as heterotaxy syndrome or situs ambiguus, which is characterized by abnormalities of the heart, liver, intestines, or spleen. These organs may be structurally abnormal or improperly positioned. In addition, affected individuals may lack a spleen (asplenia) or have multiple spleens (polysplenia). Heterotaxy syndrome results from problems establishing the left and right sides of the body during embryonic development. The severity of heterotaxy varies widely among affected individuals.\n\nPrimary ciliary dyskinesia can also lead to infertility. Vigorous movements of the flagella are necessary to propel the sperm cells forward to the female egg cell. Because their sperm do not move properly, males with primary ciliary dyskinesia are usually unable to father children. Infertility occurs in some affected females and is likely due to abnormal cilia in the fallopian tubes.\n\nAnother feature of primary ciliary dyskinesia is recurrent ear infections (otitis media), especially in young children. Otitis media can lead to permanent hearing loss if untreated. The ear infections are likely related to abnormal cilia within the inner ear.\n\nIn the respiratory tract, cilia move back and forth in a coordinated way to move mucus towards the throat. This movement of mucus helps to eliminate fluid, bacteria, and particles from the lungs. Most babies with primary ciliary dyskinesia experience breathing problems at birth, which suggests that cilia play an important role in clearing fetal fluid from the lungs. Beginning in early childhood, affected individuals develop frequent respiratory tract infections. Without properly functioning cilia in the airway, bacteria remain in the respiratory tract and cause infection. People with primary ciliary dyskinesia also have year-round nasal congestion and a chronic cough. Chronic respiratory tract infections can result in a condition called bronchiectasis, which damages the passages, called bronchi, leading from the windpipe to the lungs and can cause life-threatening breathing problems.\n\nRarely, individuals with primary ciliary dyskinesia have an accumulation of fluid in the brain (hydrocephalus), likely due to abnormal cilia in the brain.

Primary ciliary dyskinesia-14 (CILD14) is an autosomal recessive disorder characterized by recurrent respiratory infections associated with defects in ciliary inner dynein arms and axonemal disorganization (Merveille et al., 2011). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-15 (CILD15) is an autosomal recessive disorder characterized by recurrent respiratory infections associated with defects in ciliary inner dynein arms and axonemal disorganization (summary by Becker-Heck et al., 2011). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-16 (CILD16) is an autosomal recessive disorder characterized by early infantile onset of respiratory distress associated with absence of ciliary outer dynein arms (Mazor et al., 2011). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

CILD20 is an autosomal recessive ciliopathy characterized by infantile onset of chronic sinopulmonary infections resulting from immotile cilia and defective clearance. Patients may also have situs inversus or cardiac anomalies. Electron microscopy of respiratory epithelial cells shows absence of the outer dynein arms. Unlike other forms of CILD, patients with CILD20 do not appear to be infertile. For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-17 is an autosomal recessive disorder characterized by early infantile onset of respiratory distress associated with a defect in the function of ciliary outer dynein arms. Situs inversus is variable (summary by Panizzi et al., 2012). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-18 (CILD18) is an autosomal recessive disorder characterized by early infantile onset of recurrent sinopulmonary infections due to ciliary dysfunction and impaired airway clearance. Males are infertile and about half of patients have situs inversus. Electron microscopy of cilia shows a defect of the outer and inner dynein arms and impaired ciliary function (summary by Horani et al., 2012).

Primary ciliary dyskinesia-19 (CILD19) is an autosomal recessive ciliopathy characterized by chronic sinopulmonary infections, asthenospermia, and immotile cilia. Respiratory epithelial cells and sperm flagella of affected individuals lack both the inner and outer dynein arms. About 50% of patients have situs inversus (summary by Kott et al., 2012). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-21 (CILD21) is an autosomal recessive ciliopathy characterized by infantile onset of chronic sinopulmonary infections resulting from abnormal ciliary function. Electron microscopy of respiratory epithelial cells shows normal outer and inner dynein arms, but absence of nexin links and defects in the nexin-dynein regulatory complex (N-DRC). Video microscopy of patient cilia shows an increased beat frequency with decreased bending amplitude (summary by Wirschell et al., 2013). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-22 (CILD22) is an autosomal recessive disorder caused by defective structure and function of cilia or flagella. Ciliary dysfunction causes respiratory distress in term neonates, impaired mucociliary clearance, chronic cough, sinusitis, bronchiectasis, and male infertility. Defective motility of embryonic nodal cilia leads to situs abnormalities in about 50% of patients. CILD22 is characterized by defects of the inner and outer dynein arms (summary by Zariwala et al., 2013). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-23 is an autosomal recessive disorder resulting from defective ciliary motility. Affected individuals have respiratory distress and recurrent upper and lower airway infections, and they often develop bronchiectasis. About 50% of patients have situs inversus or laterality defects. Ultrastructural analysis of respiratory cilia shows defects in the outer dynein arm (summary by Hjeij et al., 2013). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-24 is an autosomal recessive disorder resulting from defects of motile cilia. It is characterized clinically by sinopulmonary infection and subfertility; situs inversus is not observed. Ultrastructural examination of mutant cilia shows defects of the central microtubule complex and radial spokes (summary by Kott et al., 2013). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-25 is an autosomal recessive disorder caused by defective ciliary movement. Affected individuals have recurrent upper and lower airway disease, bronchiectasis, and decreased fertility. About half of patients show laterality defects, including situs inversus totalis. Respiratory cilia from patients show defects in the inner and outer dynein arms (summary by Tarkar et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-26 is an autosomal recessive disorder caused by defective ciliary movement. Affected individuals have neonatal respiratory distress, recurrent upper and lower airway disease, and bronchiectasis. About half of patients show laterality defects, including situs inversus totalis. Respiratory cilia from patients show defects in the inner and outer dynein arms (summary by Austin-Tse et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-27 is an autosomal recessive disorder caused by defective ciliary movement. Affected individuals have neonatal respiratory distress, recurrent upper and lower airway disease, and bronchiectasis. Respiratory cilia from patients show defects in the inner dynein arms and nexin links. Situs inversus has not been reported in these patients (summary by Austin-Tse et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Primary ciliary dyskinesia-28 (CILD28) is an autosomal recessive disorder caused by defective ciliary movement. Affected individuals have recurrent upper and lower airway disease, bronchiectasis, and decreased fertility. About half of patients show laterality defects, including situs inversus. Respiratory cilia from patients show defects in both the inner and outer dynein arms (summary by Knowles et al., 2013). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-29 is an autosomal recessive disorder characterized by early childhood onset of recurrent respiratory infections due to defective mucociliary clearance. Patients do not have situs inversus (summary by Wallmeier et al., 2014). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see 244400.

Any primary ciliary dyskinesia in which the cause of the disease is a mutation in the CCDC151 gene.

Primary ciliary dyskinesia-33 is an autosomal recessive disorder characterized by recurrent upper and lower respiratory infections due to defective ciliary clearance and resulting in chronic lung disease. Some patients may have recurrent ear infections resulting in conductive hearing impairment. Examination of respiratory cilia shows subtle movement defects. Laterality defects have not been reported (summary by Olbrich et al., 2015). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-32 is an autosomal recessive disorder caused by defective structure and function of cilia. Ciliary dysfunction causes respiratory distress in term neonates, impaired mucociliary clearance, chronic respiratory infections, bronchiectasis, and infertility. The ciliary defect affects the central pair complex and radial spokes of the 9+2 motile cilia; affected individuals do not have situs abnormalities (summary by Jeanson et al., 2015). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia is a genetically heterogeneous autosomal recessive disorder resulting from loss of function of different parts of the primary ciliary apparatus, most often dynein arms. Kartagener (pronounced KART-agayner) syndrome is characterized by the combination of primary ciliary dyskinesia and situs inversus (270100), and occurs in approximately half of patients with ciliary dyskinesia. Since normal nodal ciliary movement in the embryo is required for normal visceral asymmetry, absence of normal ciliary movement results in a lack of definitive patterning; thus, random chance alone appears to determine whether the viscera take up the normal or reversed left-right position during embryogenesis. This explains why approximately 50% of patients, even within the same family, have situs inversus (Afzelius, 1976; El Zein et al., 2003). Genetic Heterogeneity of Primary Ciliary Dyskinesia Other forms of primary ciliary dyskinesia include CILD2 (606763), caused by mutation in the DNAAF3 gene (614566) on 19q13; CILD3 (608644), caused by mutation in the DNAH5 gene (603335) on 5p15; CILD4 (608646), mapped to 15q13; CILD5 (608647), caused by mutation in the HYDIN gene (610812) on 16q22; CILD6 (610852), caused by mutation in the TXNDC3 gene (607421) on 7p14; CILD7 (611884), caused by mutation in the DNAH11 gene (603339) on 7p15; CILD8 (612274), mapped to 15q24-q25; CILD9 (612444), caused by mutation in the DNAI2 gene (605483) on 17q25; CILD10 (612518), caused by mutation in the DNAAF2 gene (612517) on 14q21; CILD11 (612649), caused by mutation in the RSPH4A gene (612647) on 6q22; CILD12 (612650), caused by mutation in the RSPH9 gene (612648) on 6p21; CILD13 (613193), caused by mutation in the DNAAF1 gene (613190) on 16q24; CILD14 (613807), caused by mutation in the CCDC39 gene (613798) gene on 3q26; CILD15 (613808), caused by mutation in the CCDC40 gene (613799) on 17q25; CILD16 (614017), caused by mutation in the DNAL1 gene (610062) on 14q24; CILD17 (614679), caused by mutation in the CCDC103 gene (614677) on 17q21; CILD18 (614874), caused by mutation in the DNAAF5 gene (614864) on 7p22; CILD19 (614935), caused by mutation in the LRRC6 gene (614930) on 8q24; CILD20 (615067), caused by mutation in the CCDC114 gene (615038) on 19q13; CILD21 (615294), caused by mutation in the DRC1 gene (615288) on 2p23; CILD22 (615444), caused by mutation in the ZMYND10 gene (607070) on 3p21; CILD23 (615451), caused by mutation in the ARMC4 gene (615408) on 10p; CILD24 (615481), caused by mutation in the RSPH1 gene (609314) on 21q22; CILD25 (615482), caused by mutation in the DYX1C1 gene (608706) on 15q21; CILD26 (615500), caused by mutation in the C21ORF59 gene (615494) on 21q22; CILD27 (615504), caused by mutation in the CCDC65 gene (611088) on 12q13; CILD28 (615505), caused by mutation in the SPAG1 gene (603395) on 8q22; CILD29 (615872), caused by mutation in the CCNO gene (607752) on 5q11; CILD30 (616037), caused by mutation in the CCDC151 gene (615956) on 19p13; CILD32 (616481), caused by mutation in the RSPH3 gene (615876) on 6q25; CILD33 (616726), caused by mutation in the GAS8 gene (605178) on 16q24; CILD34 (617091), caused by mutation in the DNAJB13 gene (610263) on 11q13; CILD35 (617092), caused by mutation in the TTC25 gene (617095) on 17q21; CILD36 (300991), caused by mutation in the PIH1D3 gene (300933) on Xq22; CILD37 (617577), caused by mutation in the DNAH1 gene (603332) on 3p21; CILD38 (618063), caused by mutation in the CFAP300 gene (618058) on 11q22; CILD39 (618254), caused by mutation in the LRRC56 gene (618227) on 11p15; CILD40 (618300), caused by mutation in the DNAH9 gene (603330) on 17p12; CILD41 (618449), caused by mutation in the GAS2L2 gene (611398) on 17q12; CILD42 (618695), caused by mutation in the MCIDAS gene (614086) on 5q11; CILD43 (618699), caused by mutation in the FOXJ1 gene (602291) on 17q25; CILD44 (618781), caused by mutation in the NEK10 gene (618726) on 3p24; CILD45 (618801), caused by mutation in the TTC12 gene (610732) on 11q23; CILD46 (619436), caused by mutation in the STK36 gene (607652) on 2q35; CILD47 (619466), caused by mutation in the TP73 gene (601990) on 1p36; CILD48 (620032), caused by mutation in the NME5 gene (603575) on chromosome 5q31; CILD49 (620197), caused by mutation in the CFAP74 gene (620187) on chromosome 1p36; CILD50 (620356), caused by mutation in the DNAH7 gene (610061) on chromosome 2q32; CILD51 (620438), caused by mutation in the BRWD1 gene (617824) on chromosome 21q22; CILD52 (620570), caused by mutation in the DAW1 gene (620279) on chromosome 2q36; and CILD53 (620642), caused by mutation in the CLXN gene (619564) on chromosome 8q11. Ciliary abnormalities have also been reported in association with both X-linked and autosomal forms of retinitis pigmentosa. Mutations in the RPGR gene (312610), which underlie X-linked retinitis pigmentosa (RP3; 300029), are in some instances (e.g., 312610.0016) associated with recurrent respiratory infections indistinguishable from immotile cilia syndrome; see 300455. Afzelius (1979) gave an extensive review of cilia and their disorders. There are also several possibly distinct CILDs described based on the electron microscopic appearance of abnormal cilia, including CILD with transposition of the microtubules (215520), CILD with excessively long cilia (242680), and CILD with defective radial spokes (242670).

Primary ciliary dyskinesia-46 (CILD46) is characterized by recurrent sinus and respiratory infections, with reduced pulmonary function and uncoordinated beating of respiratory cilia. No situs abnormalities have been observed (Edelbusch et al., 2017). For a general phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).

Primary ciliary dyskinesia-49 (CILD49) without situs inversus is an autosomal recessive disorder characterized by the onset of recurrent respiratory infections, chronic cough, and bronchiectasis in early childhood due to defective ciliary clearance. Affected males also show infertility due to defective flagellar morphology and function. Nasal nitric oxide (NO) levels are normal and situs abnormalities are not observed (Sha et al., 2020; Biebach et al., 2022). For a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400).