Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Clinical studies and genetic linkage analysis in 64 members of a family with autosomal dominant congenital cataracts demonstrated intrafamilial variable expressivity and asymmetry between the two eyes. On the basis of 26 polymorphic phenotypic gene markers, linkage was excluded with the Duffy blood group (located on chromosome 1), haptoglobin (chromosome 16), and others. These data supported genetic heterogeneity of congenital cataracts as previous linkage assignments have included the pulverulent or Coppock cataract to chromosome 1 with Duffy and a posterior polar cataract to chromosome 16 with haptoglobin.
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PMID:Genetic linkage analysis of autosomal dominant congenital cataracts. 345 4

CZP1, a locus for autosomal dominant "zonular pulverulent" cataract, previously had been linked with the Duffy blood-group-antigen locus on chromosome 1q. Here we report genetic refinement of the CZP1 locus and show that the underlying mutation is present in GJA8, the gene for connexin50. To map the CZP1 locus we performed linkage analysis using microsatellite markers on two distantly related branches of the original Ev. pedigree, which now spans eight generations. Significantly positive two-point LOD score (Z) values were obtained for markers D1S2669 (maximum Z [Zmax] = 4.52; maximum recombination frequency [thetamax] = 0) and D1S514 (Zmax = 4.48; thetamax = 0). Multipoint analysis gave Zmax = 5.22 (thetamax = 0) at marker D1S2669. Haplotyping indicated that CZP1 probably lies in the genetic interval D1S2746-(20.6 cM)-D1S2771. Sequence analysis of the entire protein-coding region of the GJA8 gene from the pedigree detected a C-->T transition in codon 88, which introduced a novel MnlI restriction-enzyme site that also cosegregated with the cataract. This missense mutation is predicted to result in the nonconservative substitution of serine for a phylogenetically conserved proline (P88S). These studies provide the first direct evidence that GJA8 plays a vital role in the maintenance of human lens transparency and identify the genetic defect believed to underlie the first inherited disease to be linked to a human autosome.
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PMID:A missense mutation in the human connexin50 gene (GJA8) underlies autosomal dominant "zonular pulverulent" cataract, on chromosome 1q. 949 59