Clinical features and gene variant of a pedigree affected with X-linked recessive mental retardation Claes-Jensen type.
10.3760/cma.j.cn511374-20191218-00643
- VernacularTitle:一个X连锁隐性精神发育迟滞Claes-Jensen型家系的临床特征及基因变异分析
- Author:
Ning DING
1
;
Pingping ZHANG
;
Yingying MAO
;
Shuo FENG
;
Zhijie GAO
;
Qian CHEN
;
Xue ZHANG
Author Information
1. Department of Neurology, Children's Hospital, Capital Institute of Pediatrics, Beijing 100020, China. chenqianxhl@163.com.
- Publication Type:Journal Article
- MeSH:
Aged;
Female;
Histone Demethylases/genetics*;
Humans;
Male;
Mental Retardation, X-Linked/pathology*;
Mutation, Missense/genetics*;
Pedigree;
Phenotype;
Whole Exome Sequencing
- From:
Chinese Journal of Medical Genetics
2020;37(12):1352-1355
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To explore the genetic basis for a pedigree affected with X-linked recessive mental retardation Claes-Jensen type.
METHODS:Genomic DNA was extracted from peripheral blood samples of the patient, his parents (phenotypically normal) and two elder brothers with similar clinical manifestations. Whole exome sequencing was carried out for the proband, and the result was verified by Sanger sequencing.
RESULTS:The proband was found to harbor a hemizygous c.1565C>T missense variant in exon 11 of the KDM5C gene. The transition has resulted in replacement of serine by phenylalanine at position 522 (p.Ser522Phe). Sanger sequencing showed that the patient's two elder brothers and mother carried the same variant, which was predicted to be probably damaging by SIFT, PolyPhen2 and Mutation_Taster. The three affected brothers presented with similar clinical phenotypes characterized by mental retardation, speech delay, behavioral problem, self-limited epilepsy responsible to medication, short stature and microcephaly. The mother only had mild cognitive impairment and learning disability. The same variant was not found in their father and was unreported previously.
CONCLUSION:The c.1565C>T (p.Ser522Phe) of the KDM5C gene probably underlay the X-linked recessive mental retardation Claes-Jensen type in this pedigree.
