Position effect modifying gene expression in a patient with ring chromosome 14
Roberta Santos Guilherme1, Mariana Moysés-Oliveira1, Anelisa Gollo Dantas1
1Department of Morphology and Genetics, Universidade Federal de São Paulo, Rua Botucatu, 740, 04023-900, São Paulo, Brazil.
Journal of Applied Genetics
|August 29, 2015
Summary
Ring chromosome 14 in a patient, despite no gene loss, showed altered gene expression. This suggests changes in chromatin structure may cause phenotypic differences in ring chromosome disorders.
Area of Science:
- Genetics
- Molecular Biology
- Clinical Genetics
Background:
- Ring chromosomes typically cause disease through genomic material loss.
- Phenotypic alterations can occur even with complete ring chromosomes, without gene loss.
Purpose of the Study:
- To investigate gene expression changes in a patient with ring chromosome 14.
- To determine if ring chromosome configuration affects gene expression and clinical features.
Main Methods:
- Quantitative real-time polymerase chain reaction (qPCR) was used.
- Gene expression of eight chromosome 14 genes was analyzed in the patient and controls.
Main Results:
- Two genes on chromosome 14 were found to be downregulated in the patient.
- Gene copy number was normal, but expression levels were altered.
Conclusions:
- Phenotypic alterations in ring chromosome disorders may result from changes in gene expression due to chromatin architecture.
- Position effect alterations in gene expression can explain clinical features in patients with complete ring chromosomes.
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