Clinical and molecular analysis of children with central pulverulent cataract from the Arabian Peninsula.
PMID 22267527 | DOI 10.1136/bjophthalmol-2011-301053 · The British journal of ophthalmology · 2012
AIM: To clinically and genetically characterise central pulverulent cataract in a consecutive cohort of children from the Arabian Peninsula who were referred for ophthalmic evaluation. METHODS: Ophthalmic examination, homozygosity mapping in a consanguineous family and candidate gene analysis. RESULTS: All 16 children (4-16 years old, mean 9 years; seven girls and nine boys from 10 families) had bilateral central nuclear dust-like lenticular opacities. Two patients (one family) had cortical riders and six had associated strabismus. Cycloplegic retinoscopy was usually hyperopic (13/16; right eye spherical equivalent +0.50 to +6.25 dioptres, mean +3.50) but was sometimes myopic (3/16; right eye spherical equivalent -0.50 to -11.75, mean -6.50). In children with amblyopia (5/16), the cause was significant uncorrected ametropias rather than the lens opacities. Three patients had uncomplicated unilateral cataract surgery suggested by an outside second opinion that did not improve best-corrected visual acuity. Homozygosity mapping for one consanguineous family suggested the candidate gene CRYBB1. Sequencing of this gene revealed a homozygous c.171del mutation (p.N58Tfs*107) with a shared haplotype in all 16 children. In asymptomatic carrier parents from five of the six families available for careful slit-lamp examination, occasional central dot lenticular opacities were documented. CONCLUSIONS: Central pulverulent cataract in this consanguineous population does not significantly impact visual acuity during early childhood, can be associated with significant ametropias (with amblyopia and/or strabismus) and is specific for a homozygous CRYBB1 founder mutation. Primary management in children is typically spectacle correction based on cycloplegic retinoscopy to treat significant refractive error rather than paediatric cataract surgery.
Validated evidence
| Type | Entity | Source evidence | Confidence | Extractor |
|---|---|---|---|---|
| gene | CRYBB1 | “Homozygosity mapping for one consanguineous family suggested the candidate gene CRYBB1.” | 0.98 | hgnc_dict_v1 |
| phenotype | congenital cataract | “Clinical and molecular analysis of children with central pulverulent cataract from the Arabian Peninsula.” | 0.93 | phenotype_alias_lexicon_v2 |
| population | Population | “METHODS: Ophthalmic examination, homozygosity mapping in a consanguineous family and candidate gene analysis. RESULTS: All 16 children (4-16 years old, mean 9 years; seven girls and nine boys from 10 families) had bilateral central nuclear dust-like lenticular opacities. Homozygosity mapping for one consanguineous family suggested the candidate gene CRYBB1. CONCLUSIONS: Central pulverulent cataract in this consanguineous population does not significantly impact visual acuity during early childhood, can be associated with significant ametropias (with amblyopia and/or strabismus) and is specific for a homozygous CRYBB1 founder mutation.” | 0.80 | saudi_context_rules_v1 |
| variant | c.171del | “Sequencing of this gene revealed a homozygous c.171del mutation (p.N58Tfs*107) with a shared haplotype in all 16 children.” | 0.95 | hgvs_regex_v1 |
| variant | p.N58Tfs | “Sequencing of this gene revealed a homozygous c.171del mutation (p.N58Tfs*107) with a shared haplotype in all 16 children.” | 0.95 | hgvs_regex_v1 |