摘要目的 对1个瓜氨酸血症家系进行分子遗传学检测,以确诊其病因.方法 抽取患儿及其父母外周血并提取基因组DNA,应用直接测序法对患儿ASS1基因14个外显子的PCR扩增产物进行DNA测序检测.结果 患儿ASS1基因第13外显子发生纯合错义突变c.970G＞A,使第324位密码子由GGT突变为AGT,使甘氨酸替换为丝氨酸,即p.G324S,测序结果显示在该位点其父母均为杂合突变.结论 c.970G＞A纯合突变是该患儿的患病原因,父母均为该突变的携带者.

abstractsObjective To investigate potential mutation of the ASS1 gene in a male infant with acute citrullinemia type Ⅰ.Methods Genomic DNA was prepared from peripheral blood samples of the family members.Mutation analysis of the 14 ASS1 exons was carried out by PCR and direct DNA sequencing.Results A homozygous missense mutation of c.970G＞A located in exon 13,which results in p.G324S,was identified in the child.Sequencing of the parents showed a heterozygous status for the same mutation.Conclusion A missense mutation of c.970G＞A in the ASS1 gene is responsible for the pathogenesis of the disease in the infant.