The constitutional deletion of chromosome 1p36 results in a syndrome with multiple congenital anomalies and mental retardation (Shapira et al., 1997). Monosomy 1p36 is the most common terminal deletion syndrome in humans, occurring in 1 in 5,000 births (Shaffer and Lupski, 2000; Heilstedt et al., 2003). See also neurodevelopmental disorder with or without anomalies of the brain, eye, or heart (NEDBEH; 616975), which shows overlapping features and is caused by heterozygous mutation in the RERE gene (605226) on proximal chromosome 1p36. See also Radio-Tartaglia syndrome (RATARS; 619312), caused by mutation in the SPEN gene (613484) on chromosome 1p36, which shows overlapping features.

FREM1 autosomal recessive disorders include: Manitoba oculotrichoanal (MOTA) syndrome, bifid nose with or without anorectal and renal anomalies (BNAR syndrome), and isolated congenital anomalies of kidney and urinary tract (CAKUT). MOTA syndrome is characterized by an aberrant hairline (unilateral or bilateral wedge-shaped extension of the anterior hairline from the temple region to the ipsilateral eye) and anomalies of the eyes (widely spaced eyes, anophthalmia/microphthalmia and/or cryptophthalmos, colobomas of the upper eyelid, and corneopalpebral synechiae), nose (bifid or broad nasal tip), abdominal wall (omphalocele or umbilical hernia), and anus (stenosis and/or anterior displacement of the anal opening). The manifestations and degree of severity vary even among affected members of the same family. Growth and psychomotor development are normal. BNAR syndrome is characterized by a bifid or wide nasal tip, anorectal anomalies, and renal malformations (e.g., renal agenesis, renal dysplasia). Typically the eye manifestations of MOTA syndrome are absent. FREM1-CAKUT was identified in one individual with bilateral vesicoureteral reflux (VUR) and a second individual with VUR and renal hypodysplasia.

Chromosome 16p13.3deletion syndrome is a chromosome abnormality that can affect many parts of the body. People with this condition are missing a small piece (deletion) of chromosome 16 at a location designated p13.3. Although once thought to be a severe form of Rubinstein-Taybi syndrome, it is now emerging as a unique syndrome. Signs and symptoms may include failure to thrive, hypotonia (reduced muscle tone), short stature, microcephaly (unusually small head), characteristic facial features, mild to moderate intellectual disability, organ anomalies (i.e. heart and/or kidney problems), and vulnerability to infections. Chromosome testing of both parents can provide information about whether the deletion was inherited. In most cases, parents do not have any chromosome abnormalities. However, sometimes one parent has a balanced translocation where a piece of a chromosome has broken off and attached to another one with no gain or loss of genetic material. The balanced translocation normally does not cause signs or symptoms, but it increases the risk for having a child with a chromosome abnormality like a deletion. Treatment is based on the signs and symptoms present in each person.To learn more about chromosome abnormalities in general, view our GARD fact sheet on Chromosome Disorders.

Zellweger syndrome (ZS) is an autosomal recessive multiple congenital anomaly syndrome resulting from disordered peroxisome biogenesis. Affected children present in the newborn period with profound hypotonia, seizures, and inability to feed. Characteristic craniofacial anomalies, eye abnormalities, neuronal migration defects, hepatomegaly, and chondrodysplasia punctata are present. Children with this condition do not show any significant development and usually die in the first year of life (summary by Steinberg et al., 2006). For a complete phenotypic description and a discussion of genetic heterogeneity of Zellweger syndrome, see 214100. Individuals with PBDs of complementation group 14 (CG14, equivalent to CGJ) have mutations in the PEX19 gene. For information on the history of PBD complementation groups, see 214100.