Repository of Research and Investigative Information

Repository of Research and Investigative Information

Dezful University of Medical Sciences

Support for "Disease-Only" Genotypes and Excess of Homozygosity at the CYTH4 Primate-Specific GTTT-Repeat in Schizophrenia

(2017) Support for "Disease-Only" Genotypes and Excess of Homozygosity at the CYTH4 Primate-Specific GTTT-Repeat in Schizophrenia. Genetic Testing and Molecular Biomarkers. pp. 485-490. ISSN 1945-0265

Full text not available from this repository.

Official URL:


Objective: The role of short tandem repeats (STRs) in the control of gene expression among species is being increasingly understood following the identification of several instances in which certain STRs occur identically, or expand differentially, in primates versus nonprimates. These STRs may regulate genes that participate in characteristics that are associated with the divergence of primates from sibling orders (e.g., brain higher order functions). The CYTH4 gene contains the longest tetranucleotide STR in its core promoter, at 7-repeats, and links to the evolution of human and nonhuman primates. Allele and genotype distribution of this STR were studied in patients affected by schizophrenia (SCZ) and controls. Methods: High-resolution data were obtained on the allele and genotype distribution of the CYTH4 STR and a novel C>T single-nucleotide polymorphism (SNP) at its immediate upstream sequence in 255 patients with SCZ and 249 controls. Each sample was sequenced twice using the fluorescent dye termination method. Results: Novel alleles were detected at the long extreme of the GTTT-repeat, at 10- and 11-repeats, in the SCZ cases and controls. Excess of homozygosity was observed for the entire range of alleles across the GTTT-repeat and the C>T SNP in the SCZ patients in comparison with the controls (Yates corrected p<0.011). Three genotypes consisting of the 11-repeat allele (i.e., 11/11, 10/11, and 7/11) were detected only in the SCZ patients (i.e., disease-only genotypes), and contributed to 2.3 of the SCZ genotypes (Mid p exact <0.007). The frequency of the 11-repeat allele was estimated at 0.02 and 0.006 in the SCZ patients and controls, respectively (Mid p exact <0.006). Conclusion: This indicates that STR genotypes that are absent in the control group may be risk factors for SCZ. Future studies are warranted to test the significance of our findings.

Item Type: Article
Keywords: schizophrenia short tandem repeat CYTH4 exceptionally long primate-specific upstream purine complex short tandem repeats core promoter gene expression haplotypes evolution neurodegeneration humans Biochemistry & Molecular Biology Genetics & Heredity
Page Range: pp. 485-490
Journal or Publication Title: Genetic Testing and Molecular Biomarkers
Journal Index: ISI
Volume: 21
Number: 8
Identification Number:
ISSN: 1945-0265
Depositing User: مهندس مهدی شریفی

Actions (login required)

View Item View Item