Abstract: This study retrospectively analyzed the clinical data，follow-up records，and genetic findings of a child with 3-M syndrome， who was admitted to the Children's Hospital of Soochow University in July 2021 for growth retardation for nearly 8 years. Genetic testing revealed compound heterozygous mutations in the CUL7 gene：a previously reported splice-site variant c. 3355+5G>A（maternally inherited）and a novel nonsense mutation c. 4582C>T（paternally inherited）. According to ACMG guidelines，c. 4582C>T was classified as pathogenic（PVS1+PM2+PM3）and represented the first case reported globally. After one year of recombinant human growth hormone（rhGH）therapy，the patient's height increased by 6. 6 cm，but catch-up growth remained limited. This case expands the mutational spectrum of the CUL7 gene and provides novel evidence for genotype-phenotype correlation of 3-M syndrome. 

Key words: 3-M syndrome, growth retardation, CUL7 gene, recombinant human growth hormone

摘要： 回顾性分析2021年7月苏州大学附属儿童医院收治的1例因生长发育迟缓近8年入院的3-M综合征患儿的临床、随访资料及基因检测结果，显示患儿CUL7基因存在复合杂合突变：已报道的剪切位点变异c. 3355+5G>A（母源）及未报道的新无义突变c. 4582C>T（父源）。根据美国医学遗传学与基因组学学会（ACMG）标准，c. 4582C>T被判定为致病性（PVS1+PM2+PM3），为全球首次报道。经重组人生长激素（rhGH）治疗1年，患儿身高增长6. 6cm，但追赶性生长有限。该病例扩展了CUL7基因突变谱，为3-M综合征基因型-表型关联研究提供了新证据。

关键词: 3-M综合征, 生长发育迟缓, CUL7基因, rhGH