A case of neonatal Cornelia de Lange syndrome caused by a novel variant of SMC1A gene.
10.3760/cma.j.cn511374-20200530-00400
- Author:
Yanqing LI
1
;
Yuanbai WANG
;
Yuying JIANG
;
Wanyu FU
;
Meihua TAN
;
Jianlong ZHUANG
Author Information
1. Prenatal Diagnosis Center, Quanzhou Women and Children's Hospital, Fujian 362017, China. 415913261@qq.com.
- Publication Type:Journal Article
- MeSH:
Cell Cycle Proteins/genetics*;
Child;
DNA Copy Number Variations;
De Lange Syndrome/genetics*;
Humans;
Infant, Newborn;
Mutation;
Phenotype;
Whole Exome Sequencing
- From:
Chinese Journal of Medical Genetics
2021;38(11):1132-1135
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To explore the genetic etiology of a neonate with suggestive features of Cornelia de Lange Syndrome (CdLS).
METHODS:Chromosome karyotyping, copy number variation sequencing (CNV-seq) and whole exome sequencing (WES) were carried out for the child. Meanwhile, peripheral venous blood samples were taken from his parents for verifying the suspected pathogenic variants detected in the child.
RESULTS:The child has exhibited developmental delay, microcephaly, ptosis, micrognathia, and low ear setting, and was suspected as CdLS. No abnormality was found by karyotyping and CNV-seq analysis. WES has detected 5 heterogeneous variants and 1 hemizygous variant on the X chromosome. Combining the genetic pattern and result of family verification, a hemizygous C.3500T>C (p.ile1167thr) of the SMC1A gene was predicted to underlay the clinical manifestations of the patient. This variant was not recorded in the dbSNP and gnomAD database. PolyPhen2, Provean, SIFT all predicted the variant to be harmful, and PhastCons conservative prediction is was a conservative mutation. ACMG variant classification standard evidence supports are PM2, PP2, and PP3.
CONCLUSION:The novel c.3500T>C (p.Ile1167Thr) missense mutation of the SMC1A gene probably underlay the genetic etiology of CdLS in this child. Above results has enriched the mutation spectrum of CdLS type II, and facilitated clinical counseling for this family.
