Clinical and genetic analysis of a patient with isolated 17, 20 lyase deficiency presenting with pubertal gynecomastia
10.3760/cma.j.cn511374-20210528-00452
- VernacularTitle:一例表现为青春期男性乳腺发育的孤立性17，20裂解酶缺陷症患儿的临床及遗传学分析
- Author:
Hui YIN
1
;
Xiaobo CHEN
;
Ziqin LIU
;
Fuying SONG
;
Kang GAO
;
Xujing KONG
;
Baorong CHEN
Author Information
1. 首都儿科研究所附属儿童医院内分泌科，北京 100020
- Keywords:
17, 20-lyase deficiency;
CYP17A1 gene;
Puberty;
Gynecomastia
- From:
Chinese Journal of Medical Genetics
2022;39(7):718-721
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To explore the clinical and genetic basis for a patient with isolated 17, 20 lyase deficiency presenting with pubertal gynecomastia.Methods:Clinical manifestation, steroid analysis as well as genetic testing were carried out for a 14-year-old boy featuring puberty gynecomastia.Results:The patient was admitted due to puberty gynecomastia for 2 years. Physical examination showed Tanner B5, G2 and normal blood pressure. Laboratory examination showed normal range of serum potassium and blood gas. Steroid analysis revealed extremely high pregnenolone, progesterone, 17-hydropregnenolone and 17-hydroprogesterone, Correspondingly, the DHEA, androstenedione, testosterone and dihydrotestosterone were low. He was found to harbor compound heterozygous variants of CYP17A1 gene (c.1304T>C/p.F435S and c. 1346G>A/p.R449H), among which the R449H variant may result in isolated 17, 20 lyase deficiency by altering the structure of redox-partner binding site. Conclusion:Isolated 17, 20 lyase is a rare cause for puberty gynecomastia. The p. R449H variant of the CYP17A1 gene can result in isolated 17, 20 lyase deficiency.
