Abstract：
OBJECTIVE: 45,X/46,XY mosaicism is a rare condition with clinical and genetic heterogeneity and have a greatly increased risk of developing germ cell tumors. We describe a rare 45,X/46,XY Chinese girl with malignant tumors, especially focusing on the molecular genetics of gonadal tumor.
METHODS: We report a phenotypically Turner-like Chinese adolescent girl who presented primary amenorrhea and a pelvic mass as the chief complaint, which finally demonstrated dysgerminoma replacing the left gonad and gonadoblastoma arising from right gonad respectively. Her chromosome karyotype was 45,X(4)/46,XY(46); Y-chromosome microdeletions in AZFb regions were found on gonadal DNA rather than peripheral blood lymphocyte (PBL) DNA, while no variants were found in the promoter and coding region of SRY gene in both PBL and gonadal tissues. She underwent bilateral gonadectomy; no recurrence or serious complications were identified after 3 years of follow-up.
CONCLUSIONS: This case emphasizes the probable correlation between Y chromosome microdeletions in gonadal tissue and the severity of the phenotype in patients with 45,X/46,XY mosaicism and highlights the importance of clinical genetic testing at the chromosomal and molecular level.
METHODS: We report a phenotypically Turner-like Chinese adolescent girl who presented primary amenorrhea and a pelvic mass as the chief complaint, which finally demonstrated dysgerminoma replacing the left gonad and gonadoblastoma arising from right gonad respectively. Her chromosome karyotype was 45,X(4)/46,XY(46); Y-chromosome microdeletions in AZFb regions were found on gonadal DNA rather than peripheral blood lymphocyte (PBL) DNA, while no variants were found in the promoter and coding region of SRY gene in both PBL and gonadal tissues. She underwent bilateral gonadectomy; no recurrence or serious complications were identified after 3 years of follow-up.
CONCLUSIONS: This case emphasizes the probable correlation between Y chromosome microdeletions in gonadal tissue and the severity of the phenotype in patients with 45,X/46,XY mosaicism and highlights the importance of clinical genetic testing at the chromosomal and molecular level.
摘要：
目的：45，X/46，XY镶嵌是一种罕见的疾病，具有临床和遗传异质性，并且发生生殖细胞肿瘤的风险大大增加。我们描述了一个罕见的45，X/46，XY患有恶性肿瘤的中国女孩，特别是关注性腺肿瘤的分子遗传学。
方法：我们报告了一个表型类似于特纳的中国青春期女孩，她以原发性闭经和盆腔包块为主诉，最终证明无性细胞瘤分别取代了左性腺和右性腺产生的性腺母细胞瘤。她的染色体核型为45，X（4）/46，XY（46）；在性腺DNA而不是外周血淋巴细胞（PBL）DNA上发现AZFb区域的Y染色体微缺失，而PBL和性腺组织中SRY基因的启动子和编码区均未发现变异。她接受了双侧性腺切除术；随访3年后未发现复发或严重并发症。
结论：该案例强调了45,X/46,XY镶嵌患者性腺组织中Y染色体微缺失与表型严重程度之间的可能相关性，并强调了在染色体和分子水平进行临床遗传检测的重要性。
方法：我们报告了一个表型类似于特纳的中国青春期女孩，她以原发性闭经和盆腔包块为主诉，最终证明无性细胞瘤分别取代了左性腺和右性腺产生的性腺母细胞瘤。她的染色体核型为45，X（4）/46，XY（46）；在性腺DNA而不是外周血淋巴细胞（PBL）DNA上发现AZFb区域的Y染色体微缺失，而PBL和性腺组织中SRY基因的启动子和编码区均未发现变异。她接受了双侧性腺切除术；随访3年后未发现复发或严重并发症。
结论：该案例强调了45,X/46,XY镶嵌患者性腺组织中Y染色体微缺失与表型严重程度之间的可能相关性，并强调了在染色体和分子水平进行临床遗传检测的重要性。
