Missense mutations in Norrie disease gene are not associated with advancedstages of retinopathy of prematurity in Kuwaiti Arabs

Retinopathy of prematurity (ROP) is a disease characterized by retinal neov ascularization, possibly leading to retinal detachment and finally blindnes s. in a proportion of ROP cases, the disease progresses to advanced stages despite rigorous intervention. Missense mutations of the Norrie disease (ND ) gene have been associated with progression of the disease in ROP cases fr om the USA. We have investigated the presence of ND gene mutations in 102 p remature newborns of Kuwaiti Arab origin to replicate this finding in a dif ferent population/racial group. 56 (55%) of these newborns had normal eyes and served as controls. In 35 (34%) cases, the ROP regressed spontaneously during stage 1-3. In 11 (11%) cases, ROP progressed to advanced stages. A P CR-RFLP method was used to detect the mutations in exon 3 of the ND gene an d confirmed the DNA sequence by direct sequencing of the PCR product. The [ R121W] mutation of the ND gene was not detected in the premature newborns s creened from our Kuwaiti population/group. For the second mutation [L108P], a genotype (PP) was present in 98% of the premature newborns screened and only in 1 of 56 normal infants was the (LL) genotype detected. Our populati on is genetically homogenous in that genotype (PP) was detected at codon 10 8 in almost all controls and ROP cases. We did not find an association betw een the presence or absence of missense mutations of the ND gene and the ri sk of severe ROP. Copyright (C) 2000 S. Karger AG, Basel.