Abstract：
Spondyloocular syndrome (SOS) is a rare autosomal recessive skeletal and ocular disorder with variable phenotypes. It is caused by pathogenic mutation in the XYLT2 gene, which encodes the enzyme xylo-transferase, necessary for the synthesis of proteoglycan. It is characterized by generalized osteoporosis, short stature, hearing impairment, eye abnormalities, and cardiac defects. Till date only 24 cases have been reported worldwide with no cases documented from India. We subjected the patient to relevant biochemical investigations and Dual Energy X-ray Absorptiometry (DEXA) scan along with Next Generation Clinical Exome Sequencing (NGCES). We report a case of 23-year-old male who presented with recurrent long bone fractures, congenital heart defects, eye abnormalities (bilateral corneal opacities and atrophic bulbi), and short stature. In addition, our patient also had genu valgum and right-sided hydrocele which have never been reported in SOS till date. On genetic analysis, NGCES revealed a novel pathogenic frameshift variant c.191_192 delCA, p.(Thr64fs*22) in the XYLT2 gene. The patient is doing well on six monthly zoledronic acid infusions.
摘要：
脊柱眼综合征（SOS）是一种罕见的常染色体隐性遗传骨骼和眼部疾病，具有不同的表型。它是由XYLT2基因的致病性突变引起的，它编码的酶是木基转移酶,合成蛋白聚糖所必需的。它的特点是全身性骨质疏松症，身材矮小,听力障碍,眼睛异常,和心脏缺陷。迄今为止，全世界仅报告了24例病例，印度没有病例记录。我们对患者进行了相关的生化检查和双能X射线吸收测定（DEXA）扫描以及下一代临床外显子组测序（NGCES）。我们报告了一例23岁的男性，他表现为复发性长骨骨折，先天性心脏缺陷,眼睛异常（双侧角膜混浊和萎缩性球部），身材矮小。此外,我们的患者还患有Genuvalgum和右侧鞘膜积液，迄今为止从未在SOS中报告过。在遗传分析中,NGCES揭示了一种新的致病性移码变体c.191_192delCA，p.(Thr64fs*22)中的XYLT2基因。患者在6个月注射唑来膦酸后情况良好。
