产前诊断和分子细胞遗传学分析一条单纯的 21 号环状染色体，其 21q22.3 区域缺失 4.657Mb。
Prenatal diagnosis and molecular cytogenetic characterization of a pure ring chromosome 21 with a 4.657-Mb 21q22.3 deletion.
机构信息
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 University, Taipei, Taiwan; Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan; Department of Medical Laboratory Science and Biotechnology, Asia University, Taichung, Taiwan.
Department of Obstetrics and Gynecology, MacKay Memorial Hospital, Taipei, Taiwan.
出版信息
Taiwan J Obstet Gynecol. 2021 Jan;60(1):157-160. doi: 10.1016/j.tjog.2020.11.024.
OBJECTIVE
We present diagnosis and molecular cytogenetic characterization of a pure ring chromosome [r(21)] with a 4.657-Mb 21q22.3 deletion.
CASE REPORT
A 44-year-old woman underwent amniocentesis at 18 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype 46,XX,r(21)(p11.2q22.3). Prenatal ultrasound findings were unremarkable. Simultaneous array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes revealed a 4.657-Mb deletion at 21q22.3. The parental karyotypes were normal. The pregnancy was subsequently terminated, and a malformed fetus was delivered with facial dysmorphism and clinodactyly. Postnatal cytogenetic analysis of umbilical cord revealed a karyotype of 46,XX,r(21)(p11.2q22.3). aCGH analysis of umbilical cord revealed the result of arr 21q22.3 (43,427,188-48,084,156) × 1.0 with a 4.657-Mb 21q22.3 deletion encompassing 57 Online Mendelian Inheritance in Man (OMIM) genes including TRPM2, TSPEAR, COL18A1, COL6A1, COL6A2, LSS, PCNT, DIP2A, S100B and PRMT2. Metaphase fluorescence in situ hybridization (FISH) analysis of the umbilical cord fibroblasts confirmed a 21q22.3 deletion.
CONCLUSION
Prenatal diagnosis of an r(21) should include molecular cytogenetic characterization such as aCGH and FISH to determine the extent of the 21q22.3 deletion.
目的
我们介绍了一例纯环状染色体[r(21)]伴 21q22.3 缺失 4.657Mb 的诊断和分子细胞遗传学特征。
病例报告
一名 44 岁的女性因高龄接受了 18 周的羊膜穿刺术。羊膜穿刺术显示核型为 46,XX,r(21)(p11.2q22.3)。产前超声检查未见异常。对未培养的羊水细胞进行的同时(array comparative genomic hybridization，aCGH)分析显示 21q22.3 缺失 4.657Mb。父母的核型均正常。随后终止妊娠，分娩出一名面部畸形和指（趾）弯曲的畸形胎儿。脐带的产后细胞遗传学分析显示核型为 46,XX,r(21)(p11.2q22.3)。脐带的 aCGH 分析显示结果为 arr 21q22.3(43,427,188-48,084,156)×1.0，21q22.3 缺失 4.657Mb，包含 57 个在线孟德尔遗传数据库（Online Mendelian Inheritance in Man，OMIM）基因，包括 TRPM2、TSPEAR、COL18A1、COL6A1、COL6A2、LSS、PCNT、DIP2A、S100B 和 PRMT2。脐带成纤维细胞的中期荧光原位杂交（fluorescence in situ hybridization，FISH）分析证实了 21q22.3 缺失。
结论
r(21)的产前诊断应包括分子细胞遗传学特征，如 aCGH 和 FISH，以确定 21q22.3 缺失的范围。
Zotero 插件