X-linked mental retardation combined with autism caused by a novel hemizygous mutation of GRIA3 gene.
10.3760/cma.j.issn.1003-9406.2019.08.019
- Author:
Zhouxian BAI
1
;
Xiangdong KONG
Author Information
1. Genetic and Prenatal Diagnosis Center, the First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450000, China. kongxd@263.net.
- Publication Type:Journal Article
- MeSH:
Adolescent;
Autistic Disorder;
genetics;
Child;
Humans;
Intellectual Disability;
genetics;
Male;
Mental Retardation, X-Linked;
genetics;
Mutation;
Receptors, AMPA;
genetics
- From:
Chinese Journal of Medical Genetics
2019;36(8):829-833
- CountryChina
- Language:Chinese
-
Abstract:
OBJECTIVE:To explore the genetic basis for a family affected with mental retardation combined with autism.
METHODS:For the family featuring X-linked recessive inheritance of mental retardation combined with autism, clinical data and peripheral blood samples were collected. Potential mutations of genes associated with intellectual impairment were sequenced with an Ion PGM platform. Suspected mutations were verified with a PCR-Sanger sequencing method.
RESULTS:The patient with mental retardation had mild abnormal electroencephalograph(EEG), while brain MRI and CT scans showed no obvious abnormality. Two ABC (autism behavior checklist) testing scores were 73 and 66 when he was 7- and 13-year-old, respectively. A novel hemizygous mutation, c.64C>T (p.L22F), was detected in the GRIA3 gene in the patient, for which his mother was a heterozygous carrier. The mutation site was predicted to be possibly damaging and disease causing by PolyPhen_2 and MutationTaster.
CONCLUSION:The novel hemizygous c.64C>T (p.L22F) mutation of the GRIA3 gene probably underlies the phenotypes of mental retardation combined with autism in this family. Considering the variable clinical manifestation of mental retardation and genetic heterogeneity of autism, genetic testing is essential for making the correct diagnosis.
