| Congenital or infantile cataract is a sight-threatening lens defect that presents with an estimated incidence of 1-6 cases per 10 000 live births and cause 10-30 % of all blindness in children . Approximately 25 % of all cases are probably due to genetic defects, the majority of these inherited non-syndromic cataracts show autosomal dominant inheritance (AD); autosomal recessive (AR) and X linked (XR) forms are seldom observed.Classification of human congenital cataract is difficult because so many cataract phenotypes have been reported. Cataract affecting the nucleus is common, such as central pulverulent cataract,. Lamellar cataract (e.g. zonular pulverulent cataract) have been also called zonular, perinuclear or Marner's cataract; the accurate localization of the opacity is to the zonular area surrounding the embryonal nucleus. Cataract limited to the cortex and not affecting the nucleus is rare, blue dot (cerulean) cataract was the first described cataract only affecting the cortex. Cataract limited to the anterior or posterior pole of lens are called anterior or posterior cataract respectively. Opacities affecting the sutures of lens are called sutural cataract. But many cataract phenotypes were reported that the opacities affected more than one location in lens, such as "aceuliform" cataract ,"central pouchlike" cataract, and "coralliform" cataract.Development of advanced molecular biological techniques has facilitated the identification of more than 30 independent cataract loci located in ten different human chromosomes, from which 20 mutations have been identified. Mutations in more than 10 genes have been identified as genetic causes for autosomal dominant cataract (ADC); these genes include: crystalline gene (CRYAA, CRYAB, CRYBA, CRYBB, CRYGC, CRYGD), homeobox gene PITX3, the major intrinsic protein gene (MIP), beaded filament protein gene BFSP2, connexins gene (CX50, CX46). More recently, Len Bu et al. reported that mutations in the DNA-binding domain of heat-shock transcription factor 4 gene (HSF4) were associated with autosomal dominant lamellar and Marner cataract.Genetic heterogeneity of cataract is evident, more than one gene has been reported to cause the same phenotype. On the other hand, an identical mutation can result in different phenotypes. There are two major methods used in cataract research: on one hand, basing on major functional protein associated with cataractgenesis , mapping the disease gene location by hybridization; on the other hand, mapping the locus for hereditary cataract in typical family using candidate gene linkage analysis, genomic genescan , and candidate gene screening, then identify the cataract interrelated gene.In this study, we identified a four-generation family with hereditary cataracts transmitted as an autosomal dominant mode. The cataract phenotype is characterized by a large number of shiny slice-like and punctiform opacities extending radially from the nucleus, which resemble sea coral . this phenotype is similar to the coralliform cataract phenotype which first described by Nettleship. The pathogenesis of coralliform cataract is far from clear and the correlative reports are lacking, so studying the cataract in this family could help us understand better the cataract pathogenetic mechanisms in human.Part I the hereditary central coralliform cataract family23 from 38 family members received careful examination, including slit-lampexamination and photography of lens to record the cataract type. All affected members have identical phenotype: a large number of shiny slice-like and punctiform opacities extending radially from the nucleus, which resemble sea coral. Ophthalmic examination of the unaffected siblings in family did not reveal any ocular abnormalities. No other diseases aside from age-related disorders were identified by medical examination.Part II Estimation of the family inherited modelOn the basis of the pedigree and generation-to-generation transmission, autosomaldominant inheritance was supported : the equa...
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