Rauf Bushra, Irum Bushra, Kabir Firoz, Firasat Sabika, Naeem Muhammad Asif, Khan Shaheen N, Husnain Tayyab, Riazuddin Sheikh, Akram Javed, Riazuddin S Amer
The Wilmer Eye Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA; National Centre of Excellence in Molecular Biology, University of the Punjab, Lahore, Pakistan.
The Wilmer Eye Institute, Johns Hopkins University School of Medicine , Baltimore, MD, USA.
Hum Genome Var. 2016 Aug 4;3:16021. doi: 10.1038/hgv.2016.21. eCollection 2016.
Glaucoma is the second leading cause of blindness, affecting ~65 million people worldwide. We identified and ascertained a large cohort of inbred families with multiple individuals manifesting cardinal symptoms of primary congenital glaucoma (PCG) to investigate the etiology of the disease at a molecular level. Ophthalmic examinations, including slit-lamp microscopy and applanation tonometry, were performed to characterize the causal phenotype and confirm that affected individuals fulfilled the diagnostic criteria for PCG. Subsequently, exclusion analysis was completed with fluorescently labeled short tandem repeat markers, followed by Sanger sequencing to identify pathogenic variants. Exclusion analysis suggested linkage to the CYP1B1 locus, with positive two-point logarithm of odds scores in 23 families, while Sanger sequencing identified a total of 11 variants, including two novel mutations, in 23 families. All mutations segregated with the disease phenotype in their respective families. These included the following seven missense mutations: p.Y81N, p.E229K, p.R368H, p.R390H, p.W434R, p.R444Q and p.R469W, as well as one nonsense mutation, p.Q37*, and three frameshift mutations, p.W246Lfs81*, p.T404Sfs30* and p.P442Qfs15*. In conclusion, we identified a total of 11 mutations, reconfirming the genetic heterogeneity of CYP1B1 in the pathogenesis of PCG. To the best of our knowledge, this is the largest study investigating the contribution of CYP1B1 to the pathogenesis of PCG in the Pakistani population.
青光眼是导致失明的第二大主要原因，全球约有6500万人受其影响。我们识别并确定了一大群近亲家庭，这些家庭中有多名个体表现出原发性先天性青光眼（PCG）的主要症状，以便在分子水平上研究该疾病的病因。进行了眼科检查，包括裂隙灯显微镜检查和压平眼压测量，以表征致病表型，并确认受影响个体符合PCG的诊断标准。随后，使用荧光标记的短串联重复序列标记完成排除分析，接着进行桑格测序以识别致病变异。排除分析表明与CYP1B1基因座连锁，在23个家庭中两点对数优势分数为阳性，而桑格测序在23个家庭中总共鉴定出11个变异，包括两个新突变。所有突变在各自家庭中均与疾病表型共分离。这些包括以下七个错义突变：p.Y81N、p.E229K、p.R368H、p.R390H、p.W434R、p.R444Q和p.R469W，以及一个无义突变p.Q37和三个移码突变p.W246Lfs81、p.T404Sfs30和p.P442Qfs15。总之，我们共鉴定出11个突变，再次证实了CYP1B1在PCG发病机制中的遗传异质性。据我们所知，这是在巴基斯坦人群中研究CYP1B1对PCG发病机制贡献的最大规模研究。
