Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bardet-Biedl syndrome is a genetically heterogeneous multisystem disorder that causes severe visual impairment. Retinitis pigmentosa (RP), hypogonadism, digit and renal anomalies, obesity, and a variable degree of mental retardation characterize the disorder. Eight different loci have been identified on 2q31(BBS5), 3p13 (BBS3), 4q27 (BBS7), 11q13 (BBS1), 14q32 (BBS8), 15q22.3 (BBS4), 16q21 (BBS2), and 20p12 (BBS6). The ocular manifestations of Bardet-Biedl syndrome include an early and severe rod-cone dystrophy causing legal blindness in the second decade. Features of systemic phenotypic variability were proposed to distinguish patients mapped to either the BBS2, BBS3, or BBS4 loci but no phenotype-genotype correlation has been established for the ocular phenotype. We studied the three original families used for the identification of BBS2, BBS3, and BBS4 loci to define the ocular phenotypes of patients (n = 34) and obligate carriers (n = 32) using clinical examination and electroretinography (ERG). RP was severe and early in all cases. Myopia was associated with BBS3 and BBS4, but not BBS2. One patient with Bardet-Biedl syndrome also had iris and chorioretinal colobomata, features suggestive of Biemond syndrome.
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PMID:Ocular phenotypes of three genetic variants of Bardet-Biedl syndrome. 1569 Mar 72

Until recently, Bardet-Biedl syndrome was considered as a classic autosomal recessive condition. The disorder is defined by the association of the following clinical features: retinitis pigmentosa, polydactyly, obesity, hypogonadism, and possible mental retardation. This syndrome leads to multiple handicaps (visual impairment, complications of obesity, kidney failure, endocrine dysfunction). This condition, apparently clearly defined from a clinical point of view, appears to be genetically heterogenous. To date, six different genes have been identified: BBS1, BBS2, BBS4, BBS6, BBS7 and BBS8. Interestingly, this condition has recently been linked to a failure of cellular ciliogenesis. Moreover, this disorder is characterized by an additional degree of complexity, as it is the first example of triallelic inheritance described in human beings. However, this new finding appears to be less frequent than expected in this syndrome.
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PMID:[Update on Bardet-Biedl syndrome]. 1576 6

Bardet-Biedl syndrome (BBS) is a rare autosomal recessive ciliopathy characterized by obesity, postaxial polydactyly, retinitis pigmentosa, mental retardation, and kidney abnormalities. At least 19 genes have been shown to be associated with BBS, and therefore, genetic testing is highly complicated. We used an Illumina MiSeq platform for whole exome sequencing analysis of a family with strong clinical features of BBS. A homozygous c.1967_1968delTAinsC (p.Leu656fsX673; RefSeq NM_176824.2) mutation in BBS7 was identified in both affected children, while their healthy sibling and the non-consanguineous parents were heterozygous for this allele. Genotyping of 2,832 DNA samples obtained from Russian blood donors revealed 2 additional heterozygous subjects (0.07%) with the c.1967_1968delTAinsC mutation. These findings may facilitate the genetic diagnosis for Slavic BBS patients.
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PMID:Exome Sequencing of a Family with Bardet-Biedl Syndrome Identifies the Common Russian Mutation c.1967_1968delTAinsC in BBS7. 2655 28