一例先天性肾性尿崩症新生儿的AVPR2基因变异分析

Analysis of AVPR2 variant in a neonate with congenital nephrogenic diabetes insipidus

目的对1例新生儿期诊断的先天性肾性尿崩症患者及其父母进行AVPR2基因的变异检测。方法收集患儿的临床资料,采集患儿及其父母的外周血样,提取基因组DNA,用PCR扩增AVPR2基因的全部编码区并进行Sanger测序。结果患儿出生后不久即出现反复发热、多尿、血钠增高。B超随访提示患儿存在一过性肾积水和输尿管扩张,用氢氯噻嗪治疗部分有效。DNA测序发现患儿及其母亲均携带AVPR2基因第2外显子c.890-899delACCCGGAGGC大片段缺失移码变异,既往未见报道。结论AVPR2基因第2外显子c.890-899delACCCGGAGGC大片段缺失移码变异可能是患儿先天性肾性尿崩症的病因。

Objective To detect potential variant in a male neonate affected with congenital nephrogenic diabetes insipidus(CNDI).Methods Clinical data of the patient was collected.Genomic DNA was extracted from peripheral blood samples from the child and his parents.The whole coding regions of the arginine vasopressin V2 receptor(AVPR2)gene were amplified by PCR and subjected to Sanger sequencing.Results The patient presented recurrent fever and polyuria after birth.Multiple blood gas analyses indicated hypernatremia.Ultrasound showed bilateral hydronephrosis and hydroureter.The patient was partially responsive to hydrochlorothiazide.DNA analysis identified a hemizygous frameshift variant c.890-899delACCCGGAGGC in exon 2 of the AVPR2 gene in the proband.His mother was heterozygous for the same variant.Conclusion The c.890-899delACCCGGAGGC variant of the AVPR2 gene probably underlies the CNDI in the child.Above discovery has enriched to spectrum of CNDI associated variants.