患儿，男，1岁9个月，表现为46,XY性发育异常，外生殖器呈重度男性化不全表型，实验室检查及超声检查提示睾丸间质细胞及支持细胞功能良好，基因检测发现患儿PPP1R12A基因存在c.1186dupA（p.T396Nfs*17）新发致病性杂合变异。既往报道13例PPP1R12A基因变异的病例，可单独累及泌尿生殖系统或神经系统，也可累及其他系统或器官（消化、眼、心脏等）；性发育异常患者染色体核型均为46,XY，表现为不同程度的男性化不全，外生殖器、性腺及生殖管道均可受累。该文报道1例由PPP1R12A基因杂合变异所致的46,XY 性发育异常伴生长迟缓的患儿，扩大了PPP1R12A基因变异导致的临床疾病谱。

The patient was a boy aged 1 year and 9 months who presented with 46,XY disorder of sex development (DSD), with severe undermasculinization of the external genitalia. Laboratory tests and ultrasound examinations showed normal functions of Leydig cells and Sertoli cells in the testes. Genetic testing revealed a novel pathogenic heterozygous variant, c.1186dupA (p.T396Nfs*17), in the PPP1R12A gene. Thirteen cases of PPP1R12A gene variants have been reported previously. These variants may cause isolated involvement of the genitourinary or neurological systems, or affect other systems/organs including the digestive tract, eyes, heart, etc. Patients with DSD typically present with a 46,XY karyotype and variable degrees of undermasculinization involving the external genitalia, gonads, and reproductive tract. This article reports a child with 46,XY DSD accompanied by growth retardation caused by a heterozygous variant in the PPP1R12A gene, which expands the clinical disease spectrum associated with PPP1R12A gene variants.