Primary congenital glaucoma localizes to chromosome 14q24.2-24.3 in two consanguineous Pakistani families

PURPOSE Two consanguineous Pakistani families with autosomal recessive primary congenital glaucoma were recruited to identify the disease locus. METHODS Ophthalmic examinations including slit lamp biomicroscopy and applanation tonometry were employed to classify the phenotype. Blood samples were collected and genomic DNA was extracted. A genome wide scan was performed on both families with 382 polymorphic microsatellite markers. Two point LOD scores were calculated, and haplotypes were constructed to define the disease interval. RESULTS Clinical records and ophthalmic examinations suggest that affected individuals in families PKGL005 and PKGL025 have primary congenital glaucoma. Maximum two-point LOD scores of 5.88 with D14S61 at theta=0 and 6.19 with D14S43 at theta=0 were obtained for families PKGL005 and PKGL025, respectively. Haplotype analysis defined the disease locus as spanning a 6.56 cM (~4.2 Mb) genetic interval flanked by D14S289 proximally and D14S85 distally. CONCLUSIONS Linkage analysis localizes autosomal recessive primary congenital glaucoma to chromosome 14q24.2-24.3 in consanguineous Pakistani families.