一例晚期婴儿型异染性脑白质营养不良患儿的遗传学分析

目的分析1例晚期婴儿型异染性脑白质营养不良患儿的临床特征并对其进行ARSA基因的变异检测。方法对患儿及其父母ARSA基因的外显子及外显子-内含子交界区进行PCR扩增并测序。结果患儿表现为典型的晚期婴儿型异染性脑白质营养不良症状,包括运动功能倒退、芳基硫酸酯酶A缺陷、脑白质脱髓鞘样改变。患儿携带ARSA基因c.96OG>A和c.244OT复合杂合变异,分别来源于其母亲和父亲,其中c.960G>A为已知致病变异,c.244C〉T为新发现的变异。在50名正常对照中未发现相同变异。结论ARSA基因c.96OG>A和c.244C>T复合杂合变异很可能是患儿发病的原因。

Genetic analysis of a patient with late infantile metachromatic leukodystrophy

Objective To detect variants of ARSA gene in a child featuring late infantile metachromatic leukodystrophy(MLD).Methods PCR and Sanger sequencing was carried out for the patient and her parents.Results The patient had typical features of MLD including ARSA deficiency,regression of walking ability,and demyelination.Compound heterozygous variants of the ARSA gene,namely c.9600 A and c.2440 T,were detected in the patient,for which her mother and father were respectively heterozygous carriers.ARSA c.9600 A was known to be pathogenic,while ARSA c.2440 T was a novel variant.The same variants were not detected among 50 healthy controls.Conclusion The compound heterozygous variants c.9600 A and c.244C>T of the ARSA gene probably underlie the MLD in this patient.