一例携带PCNT基因复合杂合新突变的MOPDⅡ男孩病例报道及文献复习

Novel compound heterozygous mutations of the PCNT gene in one Chinese boy with microcephalic osteodysplastic primordial dwarfism type II ： case report and literature review

小头畸形-骨发育不良-原基性侏儒综合征Ⅱ型（Microcephalic or Majewski′s osteodysplastic primordial dwarfism type Ⅱ，MOPD Ⅱ）主要由中心体粒周蛋白（Pericentrin，PCNT）基因功能性突变所引起，临床上极其罕见。本文报道1例13岁男孩，因＂身高增长缓慢13年余，肤色加深半年余＂入院，除MOPD Ⅱ表现外还合并完全性生长激素缺乏症、2型糖尿病、高血压和黑棘皮病，多发牛奶咖啡斑。但头颅磁共振无动脉瘤等血管畸形。二代测序显示患者PCNT基因存在无义突变c.502C〉T（p.Gln168＊杂合突变）和c.3103C〉T（p.Arg1035＊杂合突变），均为新突变，其父携带无义突变c.3103C〉T（p.Arg1035＊杂合突变），其母携带无义突变c.502C〉T（p.Gln168＊杂合突变）。给予患儿二甲双胍片等治疗后，其血糖趋于正常，黑棘皮较治疗前减轻。针对PCNT基因突变的MOPD Ⅱ患者，需要定期评估血管异常情况。

Microcephalic or Majewski′s osteodysplastic primordial dwarfism type Ⅱ（MOPD Ⅱ）is an extremely rare genetic disease mainly caused by pericentrin（PCNT）gene mutations. This paper reported one 13-year-old boy, who was admitted because of the slow growth for more than 13 years and deepened skin color over six months. He was diagnosed as MOPD Ⅱ associated with a combination of growth hormone deficiency, type 2 diabetes, hypertension, acanthosis nigricans, multiple café-au-lait spots. On magnetic resonance imaging of brain, no vascular malformations such as aneurysms were shown. There were novel compound heterozygous mutations of PCNT gene in the patient, with the nonsense mutations of c. 502C〉T（p.Gln168＊ heterozygous variation）and c. 3103C〉T（p.Arg1035＊ heterozygous variation）. His father carried a nonsense mutation c. 3103C〉T（p.Arg1035＊ heterozygous variation）and his mother had a nonsense mutation c. 502C〉T（p.Gln168＊ heterozygous variation）. After treatment with metformin for three months, his blood glucose returned to normal, and acanthosis nigricans was improved. It seems critical to evaluate the abnormal condition of blood vessels regularly for MOPD Ⅱ patients with PCNT gene mutations.