title: Association of adenosine deaminase polymorphism with mild mental retardation.
abstract: The etiology of mild mental retardation remains undefined in about 60% of cases. Even though the causes of mild mental retardation are likely to be heterogeneous, the evidence for genetic involvement is increasing, along with the development of specific diagnostic techniques. To improve our understanding of the genetic basis of mild mental retardation, we explored the role of polymorphisms of adenosine deaminase, an enzyme that is supposed to act as a neuroregulatory protein. To this end, we conducted an association study comparing children with mild mental retardation of unknown origin with two groups of controls: (1) apparently healthy children and (2) children with moderate or severe mental retardation of known etiology. Overall, 338 participants were enrolled in the study. Cases (ie, 80 children) were more likely than controls (ie, 153 healthy children and 105 children with moderate or severe mental retardation) to have the low-activity ADA-Asn 8 (ADA(1) *2) polymorphism (P < .05) and to present the ADA(1) *2/ ADA(2) *1 haplotype. No significant differences were found with respect to adenosine deaminase polymorphisms when comparing the group with moderate or severe mental retardation of known causes and healthy controls. In conclusion, our findings suggest a possible role for a low-activity genotype (ADA-8Asn) (ADA(1) *2) of adenosine deaminase in the pathogenesis of mild mental retardation.
authors.affiliation: Department of Neurosciences, Pediatric Neurology Unit, University of Rome Tor Vergata, via Montpellier 1, 00133 Rome, Italy.
authors.forename: Patrizia
authors.initials: P
authors.lastname: Saccucci
authors.forename: Carla
authors.initials: C
authors.lastname: Arpino
authors.forename: Renata
authors.initials: R
authors.lastname: Rizzo
authors.forename: Antonella
authors.initials: A
authors.lastname: Gagliano
authors.forename: Anna
authors.initials: A
authors.lastname: Volzone
authors.forename: Cristina
authors.initials: C
authors.lastname: Lalli
authors.forename: Cinzia
authors.initials: C
authors.lastname: Galasso
authors.forename: Paolo
authors.initials: P
authors.lastname: Curatolo
mesh_terms: D000243:Adenosine Deaminase / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D019988:Children with Disabilities; D006239:Haplotypes / Q000235:genetics; D006801:Humans; D008607:Intellectual Disability / Q000201:enzymology / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012016:Reference Values; D012720:Severity of Illness Index
chemical_list: D000243:Adenosine Deaminase