Prenatal Genetic Diagnosis and Origin Analysis of Rare Complete Translocation Trisomy 18
10.13471/j.cnki.j.sun.yat-sen.univ（med.sci）.2023.0515
- VernacularTitle:罕见完全性易位型18-三体的产前遗传学诊断及溯源分析
- Author:
Yan-chou YE
1
;
Wu-bin CHEN
2
;
Xiu-jing HUANG
1
;
Rong HUANG
1
;
Ying HAO
2
;
Qun FANG
1
;
Zheng CHEN
1
;
Xiu-lan HAO
1
Author Information
1. Department of Obstetrics and Gynecology， The Seventh Affiliated Hospital， Sun Yat-sen University， Shenzhen 518107， China
2. Department of Laboratory Medicine， The Affiliated Shenzhen Maternity and Child Health care Hospital， Southern Medical University， Shenzhen 518028， China
- Publication Type:Journal Article
- Keywords:
translocation trisomy 18;
prenatal diagnosis;
G-banded karyotype;
balanced translocation;
origin analysis
- From:
Journal of Sun Yat-sen University(Medical Sciences)
2023;44(5):830-834
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo discuss the origin of rare abnormal karyotypes of fetuses with high risk of trisomy 18 revealed by non-invasive prenatal testing （NIPT） and its impact on fertility. MethodsThe cytogenetic and molecular genetic analyses were performed on the abnormal chromosomes of a prenatally diagnosed fetus with rare complete translocation trisomy 18. Using the keywords “translocation trisomy 18” or “trisomy 18 translocation” in both Chinese and English， we searched PubMed， CNKI， SinoMed， WanFang Data， CQ VIP and the Chinese Medicine database. The relevant case series were retrieved and critically appraised. ResultsG-banded karyotype analysis showed that the maternal karyotype was 46，XX，t（9；18）（q31.2；q23） and the fetal karyotype was 47， XN， t （9； 18） （q31.2；q23）mat， +18， which was a rare complete translocation type of trisomy 18. The SNP array revealed the fetus had increased copy number of chromosome 18 and two complete chromosome 18 inherited from the mother with balanced chromosomal translocation. Literature search found two children with complete translocation trisomy 18 reported abroad. Both of them had trisomy 18 phenotype and originated from the balanced translocation between parental chromosome 18 and other chromosomes. ConclusionNIPT gives an effective advance warning of trisomy 18. SNP array not only improves the detection rate of chromosomal abnormalities， but also helps identify the origin. The karyotype is still the gold standard for prenatal diagnosis.
