一个儿童早老症家系临床特征分析和致病基因研究

Analysis of clinical characteristics and causative genes of Hutchinson-Gilford progeria syndrome in a family

目的 通过对一个罕见早老症家系的分析,探讨早老症患者的临床病理学特征和遗传学因素.方法 收集1个早老症家系（2代共5名家庭成员,子女3人均为患者）3例患者的基本资料,对其进行临床检查,并对患者手部、肺脏和下颌骨进行影像学分析;同时对3例患者进行染色体核型分析,对该家系进行LMNA基因突变分析.结果 家系中的3例患者半岁左右即可见皮肤硬化症,并表现出生长严重迟缓,极度衰老面容.年长患者影像学检查显示骨质疏松,下颌骨发育不全.染色体核型分析显示,3例患者及其父母核型正常.基因突变分析显示,3例患者均为LMNA基因第9号外显子的纯合突变1579C＞T（R527C）,父母均为LMNAR527C杂合突变.结论 该早老症家系患者符合儿童早老症表型,为LMNA基因R527C纯合突变所致.

Objective To assess clinicopathological features of and genetic factors in Hutchinson-Gilford progeria syndrome （HGPS） in a family.Methods General information was collected from 3 patients with HutchinsonGilford progeria syndrome in a family,which included 5 members over 2 generations with all the 3 children affected by HGPS.All the 3 patients underwent clinical investigation,image analysis of hands,lungs and mandibles,as well as karyotype analysis of chromosomes.LMNA gene mutations were analyzed in these family members.Results All the 3 patients developed skin sclerosis with severe growth retardation and appearance of extreme aging at about 6 months of age.Image analysis showed osteoporosis and mandibular hypoplasia in the elder patient.Karyotype analysis showed no abnormality in the patients or their parents.Mutation analysis revealed a homozygous mutation 1579 C 〉 T （R527C） in exon 9 of the LMNA gene in all the patients,but a heterozygous mutation R527C in the LMNA gene in their parents.Conclusions The patients in this family present characteristic manifestations of HGPS,which may be caused by the homozygous LMNA mutation R527C.