Ulnar-Mammary syndrome with TBX3 gene mutation in a Chinese family: A case report and literature review

Zhong Nan Da Xue Xue Bao Yi Xue Ban. 2022 Dec 28;47(12):1769-1774. doi: 10.11817/j.issn.1672-7347.2022.220197.
[Article in English, Chinese]

Abstract

Ulnar-Mammary syndrome (UMS) is a rare monogenic disorder caused by mutations of the TBX3 gene. This paper reported a family of UMS. The proband, a 15-year old man, was presented with mammary gland dysplasia, ulnar limb defect, short stature, and delayed growth. Whole exome sequencing revealed a 1294_1301dup mutation in exon 6 of the TBX3 gene. Sanger sequencing was used to verify other members of the family, which suggested his mother also carried the same mutation, but merely resulting in the dysplasia of her left little finger. Notably, unilateral finger involvement without any systemic organ involvement was unusual in UMS patients. The proband then was treated with recombinant human growth hormone (rhGH) and human chorionic gonadotropin (hCG). After a year and a half, his height and secondary sexual characteristics were significantly improved. The clinical manifestations of the disease are highly heterogeneous, which is easy to be misdiagnosed and missed. When the diagnosis is unclear, genetic testing is helpful for auxiliary diagnosis.

Ulnar-Mammary综合征(Ulnar-Mammary syndrome,UMS)是由TBX3基因突变所致的一种罕见单基因遗传病。本文报告1个UMS家系,先证者为15岁男性患者,表现为乳腺发育不良、尺侧肢体缺陷、身材矮小和发育迟缓。全外显子测序发现其TBX3基因的第6外显子存在1294_1301dup变异。用Sanger测序验证家系中其他成员,结果提示患者母亲也携带同样的突变,但仅表现为左侧小指发育异常。仅单侧手指受累而无任何系统器官受累的UMS患者鲜有报道。予患者重组人生长激素(recombinant human growth hormone,rhGH)和人绒毛膜促性腺激素(human chorionic gonadotropin,hCG)治疗1年半,身高及第二性征均得到明显改善。该疾病的临床表现异质性强,容易误诊漏诊,当诊断不明时,基因检测有助于辅助诊断。.

Keywords: TBX3 gene; Ulnar-Mammary syndrome; hormone replacement therapy; phenotype.

Publication types

  • Review
  • Case Reports

MeSH terms

  • Adolescent
  • Breast Diseases* / genetics
  • East Asian People
  • Female
  • Humans
  • Male
  • Mutation
  • T-Box Domain Proteins* / genetics

Substances

  • T-Box Domain Proteins
  • TBX3 protein, human

Supplementary concepts

  • Ulnar-mammary syndrome