Clinical features and Y chromosome abnormalities in children with 45, X/46, XY mosaicism
10.3760/cma.j.cn112140-20230920-00208
- VernacularTitle:45，X/46，XY嵌合体患儿的临床特点和Y染色体异常
- Author:
Junke XIA
1
;
Chen CHEN
;
Yaqin HOU
;
Fengyan TIAN
;
Xiangdong KONG
Author Information
1. 郑州大学第一附属医院遗传与产前诊断中心，郑州450052
- Keywords:
Y chromosome;
Sex chromosome disorders;
Gonadal dysgenesis, mixed
- From:
Chinese Journal of Pediatrics
2024;62(2):165-169
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the clinical and genetic characteristics of children with 45, X/46, XY mosaicism.Methods:The retrospective study included 20 children diagnosed with 45, X/46, XY and 45, X/46, X,+mar mosaicism in the First Affiliated Hospital of Zhengzhou University from 2018 to 2022. The clinical features, gonadal pathology, treatment and follow-up were summarized. Genetic tests were performed by SRY gene test, azoospermia factor region (AZF) deletion test, copy number variation-sequencing (CNV-seq). Age at first diagnosis was compared between boys and girls using independent sample t-test. Results:The 20 patients included 3 boys and 17 girls, and the age at first diagnosis were (7.6±5.5) years, it is (2.1±1.9) years in boys, (8.7±5.4) years in girls, significantly younger for boys ( t=-3.86, P=0.004). The chief complaint was external genitalia malformation for boys, and short stature (13 cases) and dysplastic external genital for girls (4 cases). Five girls presented with features of Turner syndrome. The gonadal phenotypes included mixed gonadal dysplasia (MGD, 6 cases), complete gonadal dysplasia (CGD, 10 cases), unilateral ovotestis (2 cases), possible ovaries (1 case) and undetermined gonad (1 case). One female with dysplastic genital was reassigned to male, and the gender of the remaining cases remained unchanged. Seven females were treated with recombinant human growth hormone. The height increased by (17±7) cm during the (2.9±1.2) years follow-up. No gonadal malignancy was observed. The karyotype was 45, X/46, XY in 16 cases, and 45, X/46, X,+mar in 4 cases. All of the 4 marker chromosomes were derived from Y chromosome confirmed by CNV-seq. SRY gene was detected in all 20 patients genome, and AZF deletion was found in 7 girls. Conclusions:45, X/46, XY mosaicism presented with dysplastic external genital or female with remarkable short stature. Gonadal phenotypes included MGD, CGD and ovotestis. AZF microdeletions were found in the majority of female cases.
