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Adenylosuccinate lyase deficiency(ADSLD)

MedGen UID:
78641
Concept ID:
C0268126
Disease or Syndrome
Synonyms: Adenylosuccinase Deficiency; ADSLD
SNOMED CT: Deficiency of adenylosuccinate lyase (15285008); Adenylosuccinate lyase deficiency (15285008); Succinylpurinemic autism (15285008); Succinyladenosinuria (15285008); Adenylosuccinate deficiency (15285008); ASase - Adenylosuccinate lyase deficiency (15285008)
Modes of inheritance:
Autosomal recessive inheritance
MedGen UID:
141025
Concept ID:
C0441748
Intellectual Product
Source: Orphanet
A mode of inheritance that is observed for traits related to a gene encoded on one of the autosomes (i.e., the human chromosomes 1-22) in which a trait manifests in individuals with two pathogenic alleles, either homozygotes (two copies of the same mutant allele) or compound heterozygotes (whereby each copy of a gene has a distinct mutant allele).
 
Gene (location): ADSL (22q13.1)
 
Monarch Initiative: MONDO:0007068
OMIM®: 103050
Orphanet: ORPHA46

Definition

Adenylosuccinase deficiency is an autosomal recessive inborn error of metabolism caused by an enzymatic defect in de novo purine synthesis (DNPS) pathway. ADSL deficiency leads to the accumulation of toxic intermediates, including succinyladenosine (S-Ado) and succinylaminoimidazole carboxamide riboside (SAICAr) in body fluids. There are 3 major phenotypic forms of the disorder that correlate with different values of the S-Ado and SAICAr concentration ratios (S-Ado/SAICAr) in the cerebrospinal fluid. These include the most severe fatal neonatal encephalopathy (S-Ado/SAICAr ratio less than 1); childhood form (type I) with severe psychomotor retardation (S-Ado/SAICAr ratio close to 1), and a milder form (type II) with psychomotor retardation or hypotonia (S-Ado/SAICAr ratio greater than 2) (summary by Baresova et al., 2012). [from OMIM]

Additional description

From MedlinePlus Genetics
Adenylosuccinate lyase deficiency is a neurological disorder that causes brain dysfunction (encephalopathy) leading to delayed development of mental and movement abilities (psychomotor delay), autistic characteristics that affect communication and social interaction, and seizures. A key feature that can help with diagnosis of this condition is the presence of chemicals called succinylaminoimidazole carboxamide riboside (SAICAr) and succinyladenosine (S-Ado) in body fluids.

Adenylosuccinate lyase deficiency is classified into three forms based on the severity of the signs and symptoms. The most severe is the neonatal form. Signs and symptoms of this form can be detected at or before birth and can include impaired growth during fetal development and a small head size (microcephaly). Affected newborns have severe encephalopathy, which leads to a lack of movement, difficulty feeding, and life-threatening respiratory problems. Some affected babies develop seizures that do not improve with treatment. Because of the severity of the encephalopathy, infants with this form of the condition generally do not survive more than a few weeks after birth.

Adenylosuccinate lyase deficiency type I (also known as the severe form) is the most common. The signs and symptoms of this form begin in the first months of life. Affected babies have severe psychomotor delay, weak muscle tone (hypotonia), and microcephaly. Many affected infants develop recurrent seizures that are difficult to treat, and some exhibit autistic traits, such as repetitive actions and a lack of eye contact.

In individuals with adenylosuccinate lyase deficiency type II (also known as the moderate or mild form), development is typically normal for the first few years of life but then slows. Psychomotor delay is considered mild or moderate. Some children with this form of the condition develop seizures and autistic traits.  https://medlineplus.gov/genetics/condition/adenylosuccinate-lyase-deficiency

Clinical features

From HPO
Elevated urinary succinylaminoimidazole carboxamide riboside level
MedGen UID:
1054637
Concept ID:
CN376986
Finding
Presence of succinylaminoimidazole carboxamide riboside (SAICAr). SAICAr is a toxic intermediate metabolite of purine synthesis.
Growth delay
MedGen UID:
99124
Concept ID:
C0456070
Pathologic Function
A deficiency or slowing down of growth pre- and postnatally.
Low-set ears
MedGen UID:
65980
Concept ID:
C0239234
Congenital Abnormality
Upper insertion of the ear to the scalp below an imaginary horizontal line drawn between the inner canthi of the eye and extending posteriorly to the ear.
Aggressive behavior
MedGen UID:
1375
Concept ID:
C0001807
Individual Behavior
Behavior or an act aimed at harming a person, animal, or physical property (e.g., acts of physical violence; shouting, swearing, and using harsh language; slashing someone's tires).
Autism
MedGen UID:
13966
Concept ID:
C0004352
Mental or Behavioral Dysfunction
Autism, the prototypic pervasive developmental disorder (PDD), is usually apparent by 3 years of age. It is characterized by a triad of limited or absent verbal communication, a lack of reciprocal social interaction or responsiveness, and restricted, stereotypic, and ritualized patterns of interests and behavior (Bailey et al., 1996; Risch et al., 1999). 'Autism spectrum disorder,' sometimes referred to as ASD, is a broader phenotype encompassing the less severe disorders Asperger syndrome (see ASPG1; 608638) and pervasive developmental disorder, not otherwise specified (PDD-NOS). 'Broad autism phenotype' includes individuals with some symptoms of autism, but who do not meet the full criteria for autism or other disorders. Mental retardation coexists in approximately two-thirds of individuals with ASD, except for Asperger syndrome, in which mental retardation is conspicuously absent (Jones et al., 2008). Genetic studies in autism often include family members with these less stringent diagnoses (Schellenberg et al., 2006). Levy et al. (2009) provided a general review of autism and autism spectrum disorder, including epidemiology, characteristics of the disorder, diagnosis, neurobiologic hypotheses for the etiology, genetics, and treatment options. Genetic Heterogeneity of Autism Autism is considered to be a complex multifactorial disorder involving many genes. Accordingly, several loci have been identified, some or all of which may contribute to the phenotype. Included in this entry is AUTS1, which has been mapped to chromosome 7q22. Other susceptibility loci include AUTS3 (608049), which maps to chromosome 13q14; AUTS4 (608636), which maps to chromosome 15q11; AUTS6 (609378), which maps to chromosome 17q11; AUTS7 (610676), which maps to chromosome 17q21; AUTS8 (607373), which maps to chromosome 3q25-q27; AUTS9 (611015), which maps to chromosome 7q31; AUTS10 (611016), which maps to chromosome 7q36; AUTS11 (610836), which maps to chromosome 1q41; AUTS12 (610838), which maps to chromosome 21p13-q11; AUTS13 (610908), which maps to chromosome 12q14; AUTS14A (611913), which has been found in patients with a deletion of a region of 16p11.2; AUTS14B (614671), which has been found in patients with a duplication of a region of 16p11.2; AUTS15 (612100), associated with mutation in the CNTNAP2 gene (604569) on chromosome 7q35-q36; AUTS16 (613410), associated with mutation in the SLC9A9 gene (608396) on chromosome 3q24; AUTS17 (613436), associated with mutation in the SHANK2 gene (603290) on chromosome 11q13; AUTS18 (615032), associated with mutation in the CHD8 gene (610528) on chromosome 14q11; AUTS19 (615091), associated with mutation in the EIF4E gene (133440) on chromosome 4q23; and AUTS20 (618830), associated with mutation in the NLGN1 gene (600568) on chromosome 3q26. (NOTE: the symbol 'AUTS2' has been used to refer to a gene on chromosome 7q11 (KIAA0442; 607270) and therefore is not used as a part of this autism locus series.) There are several X-linked forms of autism susceptibility: AUTSX1 (300425), associated with mutations in the NLGN3 gene (300336); AUTSX2 (300495), associated with mutations in NLGN4 (300427); AUTSX3 (300496), associated with mutations in MECP2 (300005); AUTSX4 (300830), associated with variation in the region on chromosome Xp22.11 containing the PTCHD1 gene (300828); AUTSX5 (300847), associated with mutations in the RPL10 gene (312173); and AUTSX6 (300872), associated with mutation in the TMLHE gene (300777). A locus on chromosome 2q (606053) associated with a phenotype including intellectual disability and speech deficits was formerly designated AUTS5. Folstein and Rosen-Sheidley (2001) reviewed the genetics of autism.
Hemiplegia
MedGen UID:
9196
Concept ID:
C0018991
Sign or Symptom
Paralysis (complete loss of muscle function) in the arm, leg, and in some cases the face on one side of the body.
Spasticity
MedGen UID:
7753
Concept ID:
C0026838
Sign or Symptom
A motor disorder characterized by a velocity-dependent increase in tonic stretch reflexes with increased muscle tone, exaggerated (hyperexcitable) tendon reflexes.
Myoclonus
MedGen UID:
10234
Concept ID:
C0027066
Finding
Very brief, involuntary random muscular contractions occurring at rest, in response to sensory stimuli, or accompanying voluntary movements.
Seizure
MedGen UID:
20693
Concept ID:
C0036572
Sign or Symptom
A seizure is an intermittent abnormality of nervous system physiology characterized by a transient occurrence of signs and/or symptoms due to abnormal excessive or synchronous neuronal activity in the brain.
Self-mutilation
MedGen UID:
19925
Concept ID:
C0036601
Injury or Poisoning
Deliberate harm to one's body resulting in tissue damage, without a conscious intent to die.
Opisthotonus
MedGen UID:
56246
Concept ID:
C0151818
Sign or Symptom
Cerebral atrophy
MedGen UID:
116012
Concept ID:
C0235946
Disease or Syndrome
Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum.
Hyperactivity
MedGen UID:
98406
Concept ID:
C0424295
Finding
Hyperactivity is a condition characterized by constant and unusually high levels of activity, even in situations where it is deemed inappropriate.
Inappropriate laughter
MedGen UID:
98407
Concept ID:
C0424304
Finding
Laughing that may be excessive and/or inappropriate in context (e.g., laughing at a funeral while others are crying).
Delayed speech and language development
MedGen UID:
105318
Concept ID:
C0454644
Finding
A degree of language development that is significantly below the norm for a child of a specified age.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Inability to walk
MedGen UID:
107860
Concept ID:
C0560046
Finding
Incapability to ambulate.
Cerebellar atrophy
MedGen UID:
196624
Concept ID:
C0740279
Disease or Syndrome
Cerebellar atrophy is defined as a cerebellum with initially normal structures, in a posterior fossa with normal size, which displays enlarged fissures (interfolial spaces) in comparison to the foliae secondary to loss of tissue. Cerebellar atrophy implies irreversible loss of tissue and result from an ongoing progressive disease until a final stage is reached or a single injury, e.g. an intoxication or infectious event.
Gait ataxia
MedGen UID:
155642
Concept ID:
C0751837
Sign or Symptom
A type of ataxia characterized by the impairment of the ability to coordinate the movements required for normal walking. Gait ataxia is characteirzed by a wide-based staggering gait with a tendency to fall.
Reduced eye contact
MedGen UID:
303190
Concept ID:
C1445953
Finding
A reduced frequency or duration of eye contact.
Severe global developmental delay
MedGen UID:
332436
Concept ID:
C1837397
Finding
A severe delay in the achievement of motor or mental milestones in the domains of development of a child.
Happy demeanor
MedGen UID:
344654
Concept ID:
C1856115
Finding
A conspicuously happy disposition, characterized by frequent smiling and laughing, which may be contextually inappropriate or unrelated to the situation.
Brisk reflexes
MedGen UID:
382164
Concept ID:
C2673700
Finding
Tendon reflexes that are noticeably more active than usual (conventionally denoted 3+ on clinical examination). Brisk reflexes may or may not indicate a neurological lesion. They are distinguished from hyperreflexia by the fact that hyerreflexia is characterized by hyperactive repeating (clonic) reflexes, which are considered to be always abnormal.
Cerebral hypomyelination
MedGen UID:
383084
Concept ID:
C2677328
Finding
Reduced amount of myelin in the nervous system resulting from defective myelinogenesis in the white matter of the central nervous system.
Intellectual disability
MedGen UID:
811461
Concept ID:
C3714756
Mental or Behavioral Dysfunction
Intellectual disability, previously referred to as mental retardation, is characterized by subnormal intellectual functioning that occurs during the developmental period. It is defined by an IQ score below 70.
CNS hypomyelination
MedGen UID:
892446
Concept ID:
C4025616
Finding
Reduced amount of myelin in the central nervous system resulting from defective myelinogenesis.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Brachycephaly
MedGen UID:
113165
Concept ID:
C0221356
Congenital Abnormality
An abnormality of skull shape characterized by a decreased anterior-posterior diameter. That is, a cephalic index greater than 81%. Alternatively, an apparently shortened anteroposterior dimension (length) of the head compared to width.
Muscular atrophy
MedGen UID:
892680
Concept ID:
C0541794
Pathologic Function
The presence of skeletal muscular atrophy (which is also known as amyotrophy).
Prominent metopic ridge
MedGen UID:
387953
Concept ID:
C1857949
Finding
Vertical bony ridge positioned in the midline of the forehead.
Generalized hypotonia
MedGen UID:
346841
Concept ID:
C1858120
Finding
Generalized muscular hypotonia (abnormally low muscle tone).
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
Wide mouth
MedGen UID:
44238
Concept ID:
C0024433
Congenital Abnormality
Distance between the oral commissures more than 2 SD above the mean. Alternatively, an apparently increased width of the oral aperture (subjective).
Smooth philtrum
MedGen UID:
222980
Concept ID:
C1142533
Finding
Flat skin surface, with no ridge formation in the central region of the upper lip between the nasal base and upper vermilion border.
Anteverted nares
MedGen UID:
326648
Concept ID:
C1840077
Finding
Anteriorly-facing nostrils viewed with the head in the Frankfurt horizontal and the eyes of the observer level with the eyes of the subject. This gives the appearance of an upturned nose (upturned nasal tip).
Short nose
MedGen UID:
343052
Concept ID:
C1854114
Finding
Distance from nasion to subnasale more than two standard deviations below the mean, or alternatively, an apparently decreased length from the nasal root to the nasal tip.
Long philtrum
MedGen UID:
351278
Concept ID:
C1865014
Finding
Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border.
Thin upper lip vermilion
MedGen UID:
355352
Concept ID:
C1865017
Finding
Height of the vermilion of the upper lip in the midline more than 2 SD below the mean. Alternatively, an apparently reduced height of the vermilion of the upper lip in the frontal view (subjective).
Nystagmus
MedGen UID:
45166
Concept ID:
C0028738
Disease or Syndrome
Rhythmic, involuntary oscillations of one or both eyes related to abnormality in fixation, conjugate gaze, or vestibular mechanisms.
Strabismus
MedGen UID:
21337
Concept ID:
C0038379
Disease or Syndrome
A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.

Term Hierarchy

CClinical test,  RResearch test,  OOMIM,  GGeneReviews,  VClinVar  
  • CROGVAdenylosuccinate lyase deficiency
Follow this link to review classifications for Adenylosuccinate lyase deficiency in Orphanet.

Professional guidelines

PubMed

Cakmak Celik F, Ozlu MM, Ceylaner S
Clin Neurol Neurosurg 2021 Mar;202:106506. Epub 2021 Jan 19 doi: 10.1016/j.clineuro.2021.106506. PMID: 33497949
Zikanova M, Krijt J, Skopova V, Krijt M, Baresova V, Kmoch S
Clin Biochem 2015 Jan;48(1-2):2-7. Epub 2014 Oct 23 doi: 10.1016/j.clinbiochem.2014.10.004. PMID: 25445730
Marie S, Flipsen JW, Duran M, Poll-The BT, Beemer FA, Bosschaart AN, Vincent MF, Van den Berghe G
Prenat Diagn 2000 Jan;20(1):33-6. doi: 10.1002/(sici)1097-0223(200001)20:1<33::aid-pd751>3.0.co;2-3. PMID: 10701848

Recent clinical studies

Etiology

Cutillo G, Masnada S, Lesca G, Ville D, Accorsi P, Giordano L, Pichiecchio A, Valente M, Borrelli P, Ferraro OE, Veggiotti P
Epilepsia Open 2024 Feb;9(1):106-121. Epub 2023 Nov 27 doi: 10.1002/epi4.12837. PMID: 37842880Free PMC Article
Jurecka A, Zikanova M, Kmoch S, Tylki-Szymańska A
J Inherit Metab Dis 2015 Mar;38(2):231-42. Epub 2014 Aug 12 doi: 10.1007/s10545-014-9755-y. PMID: 25112391Free PMC Article
Jurecka A, Zikanova M, Jurkiewicz E, Tylki-Szymańska A
Neuropediatrics 2014 Feb;45(1):50-5. Epub 2013 Mar 16 doi: 10.1055/s-0033-1337335. PMID: 23504561
Jurecka A, Jurkiewicz E, Tylki-Szymanska A
Eur J Pediatr 2012 Jan;171(1):131-8. Epub 2011 May 31 doi: 10.1007/s00431-011-1503-9. PMID: 21625931
Micheli V, Camici M, Tozzi MG, Ipata PL, Sestini S, Bertelli M, Pompucci G
Curr Top Med Chem 2011;11(8):923-47. doi: 10.2174/156802611795347645. PMID: 21401501

Diagnosis

Fenton AR, Janowitz HN, Franklin LP, Young RG, Moro CA, DeGennaro MV, McReynolds MR, Wang W, Hanna-Rose W
Mol Genet Metab 2023 Nov;140(3):107686. Epub 2023 Aug 15 doi: 10.1016/j.ymgme.2023.107686. PMID: 37607437Free PMC Article
Dewulf JP, Marie S, Nassogne MC
Mol Genet Metab 2022 Jul;136(3):190-198. Epub 2021 Dec 30 doi: 10.1016/j.ymgme.2021.12.016. PMID: 34998670
Mastrogiorgio G, Macchiaiolo M, Buonuomo PS, Bellacchio E, Bordi M, Vecchio D, Brown KP, Watson NK, Contardi B, Cecconi F, Tartaglia M, Bartuli A
Orphanet J Rare Dis 2021 Mar 1;16(1):112. doi: 10.1186/s13023-021-01731-6. PMID: 33648541Free PMC Article
Jurecka A, Zikanova M, Kmoch S, Tylki-Szymańska A
J Inherit Metab Dis 2015 Mar;38(2):231-42. Epub 2014 Aug 12 doi: 10.1007/s10545-014-9755-y. PMID: 25112391Free PMC Article
Spiegel EK, Colman RF, Patterson D
Mol Genet Metab 2006 Sep-Oct;89(1-2):19-31. Epub 2006 Jul 12 doi: 10.1016/j.ymgme.2006.04.018. PMID: 16839792

Therapy

Chen BC, Balasubramaniam S, McGown IN, O'Neill JP, Chng GS, Keng WT, Ngu LH, Duley JA
Brain Dev 2014 Aug;36(7):593-600. Epub 2013 Sep 18 doi: 10.1016/j.braindev.2013.08.013. PMID: 24055166
van Werkhoven MA, Duley JA, McGown I, Munce T, Freeman JL, Pitt JJ
Dev Med Child Neurol 2013 Nov;55(11):1060-4. Epub 2013 Aug 13 doi: 10.1111/dmcn.12244. PMID: 23937257
Pérez-Dueñas B, Sempere A, Campistol J, Alonso-Colmenero I, Díez M, González V, Merinero B, Desviat LR, Artuch R
Eur J Paediatr Neurol 2012 Jul;16(4):343-8. Epub 2011 Sep 7 doi: 10.1016/j.ejpn.2011.08.008. PMID: 21903433
Jurecka A, Tylki-Szymanska A, Zikanova M, Krijt J, Kmoch S
J Inherit Metab Dis 2008 Dec;31 Suppl 2:S329-32. Epub 2008 Jul 12 doi: 10.1007/s10545-008-0904-z. PMID: 18649008
Sebesta I, Krijt J, Kmoch S, Hartmannová H, Wojda M, Zeman J
J Inherit Metab Dis 1997 Jul;20(3):343-4. doi: 10.1023/a:1005361408031. PMID: 9266351

Prognosis

Cutillo G, Masnada S, Lesca G, Ville D, Accorsi P, Giordano L, Pichiecchio A, Valente M, Borrelli P, Ferraro OE, Veggiotti P
Epilepsia Open 2024 Feb;9(1):106-121. Epub 2023 Nov 27 doi: 10.1002/epi4.12837. PMID: 37842880Free PMC Article
Mastrogiorgio G, Macchiaiolo M, Buonuomo PS, Bellacchio E, Bordi M, Vecchio D, Brown KP, Watson NK, Contardi B, Cecconi F, Tartaglia M, Bartuli A
Orphanet J Rare Dis 2021 Mar 1;16(1):112. doi: 10.1186/s13023-021-01731-6. PMID: 33648541Free PMC Article
Jurecka A, Zikanova M, Kmoch S, Tylki-Szymańska A
J Inherit Metab Dis 2015 Mar;38(2):231-42. Epub 2014 Aug 12 doi: 10.1007/s10545-014-9755-y. PMID: 25112391Free PMC Article
Jurecka A, Zikanova M, Jurkiewicz E, Tylki-Szymańska A
Neuropediatrics 2014 Feb;45(1):50-5. Epub 2013 Mar 16 doi: 10.1055/s-0033-1337335. PMID: 23504561
Van den Berghe G, Vincent MF, Jaeken J
J Inherit Metab Dis 1997 Jun;20(2):193-202. doi: 10.1023/a:1005304722259. PMID: 9211192

Clinical prediction guides

Mastrogiorgio G, Macchiaiolo M, Buonuomo PS, Bellacchio E, Bordi M, Vecchio D, Brown KP, Watson NK, Contardi B, Cecconi F, Tartaglia M, Bartuli A
Orphanet J Rare Dis 2021 Mar 1;16(1):112. doi: 10.1186/s13023-021-01731-6. PMID: 33648541Free PMC Article
Jurecka A, Zikanova M, Kmoch S, Tylki-Szymańska A
J Inherit Metab Dis 2015 Mar;38(2):231-42. Epub 2014 Aug 12 doi: 10.1007/s10545-014-9755-y. PMID: 25112391Free PMC Article
Gitiaux C, Ceballos-Picot I, Marie S, Valayannopoulos V, Rio M, Verrieres S, Benoist JF, Vincent MF, Desguerre I, Bahi-Buisson N
Eur J Hum Genet 2009 Jan;17(1):133-6. Epub 2008 Oct 1 doi: 10.1038/ejhg.2008.174. PMID: 18830228Free PMC Article
Salerno C, Crifò C
Nucleosides Nucleotides Nucleic Acids 2004 Oct;23(8-9):1253-5. doi: 10.1081/NCN-200027513. PMID: 15571240
Van den Berghe G, Bontemps F, Vincent MF, Van den Bergh F
Prog Neurobiol 1992 Nov;39(5):547-61. doi: 10.1016/0301-0082(92)90006-z. PMID: 1529104

Recent systematic reviews

Cutillo G, Masnada S, Lesca G, Ville D, Accorsi P, Giordano L, Pichiecchio A, Valente M, Borrelli P, Ferraro OE, Veggiotti P
Epilepsia Open 2024 Feb;9(1):106-121. Epub 2023 Nov 27 doi: 10.1002/epi4.12837. PMID: 37842880Free PMC Article

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