Department of Obstetrics and Gynecology, MacKay Memorial Hospital, Taipei, Taiwan; Department of Medical Research, MacKay Memorial Hospital, Taipei, Taiwan; School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan; Institute of Clinical and Community Health Nursing, National Yang Ming Chiao Tung University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan; Department of Medical Laboratory Science and Biotechnology, College of Medical and Health Science, Asia University, Taichung, Taiwan.
Department of Obstetrics and Gynecology, MacKay Memorial Hospital, Taipei, Taiwan.
Taiwan J Obstet Gynecol. 2024 Jul;63(4):561-564. doi: 10.1016/j.tjog.2024.05.010.
We present prenatal diagnosis of familial 3p26.3p25.3 deletion in a pregnancy associated with a favorable fetal outcome and asymptomatic carrier parent and family members in three generations.
A 35-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age and the carrier of distal 3p deletion. She was phenotypically normal, and there was no family history of congenital anomalies. Amniocentesis revealed a karyotype of 46,XY,del(3)(p26.1). Repeat amniocentesis at 21 weeks of gestation revealed a karyotype of 46,XY,del(3)(p25.3). Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes showed the result of arr 3p26.3p25.3 (117,735-8,709,972) × 1.0 [GRCh37 (hg19)] with an 8.59-Mb deletion of 3p26.3p25.3 encompassing 14 OMIM genes of CHL1, CNTN6, CNTN4, IL5RA, TRNT1, CRBN, SETMAR, SUMF1, ITPR1, BHLHE40, ARL8B, GRM7, LMCD1 and SSUH2. Cytogenetic analysis of parental bloods revealed a karyotype of 46,XX,del (3) (p25.3) in the mother and 46,XY in the father. The woman's 69-year-old mother and her 2-year-old elder son carried the same aberrant chromosome of 3p25.3→p26.3 deletion by conventional cytogenetic analysis but manifested no phenotypic abnormality. aCGH analysis of the peripheral bloods showed that the woman's mother and her elder son had the same 8.59-Mb deletion of 3p26.3p25.3. The woman was advised to continue the pregnancy. At 39 weeks of gestation, a 3040-g healthy male baby was delivered. When follow-up at age 2½ years, the neonate was normal in development and showed no apparent phenotypic abnormality.
Distal 3p deletion of 3p26.3p25.3 involving the OMIM genes from CHL1 to SSUH2 can be associated with no apparent phenotypic abnormality.
我们报告了一例家族性 3p26.3p25.3 缺失的产前诊断，该缺失与妊娠相关，胎儿结局良好，无症状携带者父母和三代家族成员均存在该缺失。
一名 35 岁、孕 2 产 1 的女性因高龄和携带远端 3p 缺失而接受了羊膜穿刺术。她表型正常，无先天性畸形家族史。羊膜穿刺术显示核型为 46,XY,del(3)(p26.1)。21 周妊娠时的重复羊膜穿刺术显示核型为 46,XY,del(3)(p25.3)。从未培养的羊水细胞中提取的 DNA 的同时进行的 array 比较基因组杂交 (aCGH) 分析显示结果为 arr 3p26.3p25.3(117,735-8,709,972)×1.0[GRCh37(hg19)]，存在 3p26.3p25.3 的 8.59-Mb 缺失，包含 14 个 OMIM 基因 CHL1、CNTN6、CNTN4、IL5RA、TRNT1、CRBN、SETMAR、SUMF1、ITPR1、BHLHE40、ARL8B、GRM7、LMCD1 和 SSUH2。父母血液的细胞遗传学分析显示母亲的核型为 46,XX,del(3)(p25.3)，父亲的核型为 46,XY。这位 69 岁的母亲和她 2 岁的大儿子通过常规细胞遗传学分析携带相同的 3p25.3→p26.3 缺失异常染色体，但表现出无表型异常。外周血的 aCGH 分析显示，该女性的母亲和她的大儿子均存在相同的 3p26.3p25.3 的 8.59-Mb 缺失。建议该女性继续妊娠。在 39 周妊娠时，分娩出 3040g 的健康男婴。随访至 2 岁半时，新生儿发育正常，无明显表型异常。
涉及 CHL1 至 SSUH2 的 OMIM 基因的远端 3p26.3p25.3 缺失可能与无明显表型异常相关。
