RESUMO
Autosomal recessive retinitis pigmentosa (arRP) is a genetically and clinically heterogeneous and progressive degenerative disorder of the retina, leading usually to severe visual handicap in adulthood. To date, disease loci/genes have been mapped/identified only in a minority of cases. DNA samples were collected from 20 large consanguineous Indian families, in which arRP segregated and that were suitable for homozygosity mapping of the disease locus. After excluding linkage to all known arRP loci, a genome-wide scan was initiated. In two families, homozygosity mapping, haplotype analysis, and linkage data mapped the disease locus (RP22) in an approximately 16-cM region between D16S287 and D16S420 on the proximal short arm of chromosome 16. No mutation has been found by direct sequencing in the gene (CRYM) encoding micron crystallin, which maps in the critical region.
Assuntos
Cromossomos Humanos Par 16 , Genes Recessivos , Homozigoto , Retinose Pigmentar/genética , Mapeamento Cromossômico , Consanguinidade , Cristalinas/genética , Ligação Genética , Haplótipos , Humanos , Repetições de Microssatélites , Linhagem , Cristalinas muRESUMO
The first 500 posterior chamber lenses inserted in the capsular bag, have been analysed in detail. The cases included in this study were developmental, traumatic and complicated cataracts in addition to senile cataract. The follow-up ranged from 6 months to 2 years. Although posterior capsule rupture occurred in 23 cases, the lens was inserted in 12 cases with a small tear. In general the complications were found to be minimal and visual recovery was good in more than 80% of the cases. The only problems we have been facing were thickening of the posterior capsule (11.6%), high astigmatism (12.2%), pupillary capture (5.6%) and decentering of the lens (2.8%).
