Recurrent HERV-H-mediated 3q13.2-q13.31 deletions cause a syndrome of hypotonia and motor, language, and cognitive delays.
Hum Mutat
; 34(10): 1415-23, 2013 Oct.
Article
in En
| MEDLINE
| ID: mdl-23878096
ABSTRACT
We describe the molecular and clinical characterization of nine individuals with recurrent, 3.4-Mb, de novo deletions of 3q13.2-q13.31 detected by chromosomal microarray analysis. All individuals have hypotonia and language and motor delays; they variably express mild to moderate cognitive delays (8/9), abnormal behavior (7/9), and autism spectrum disorders (3/9). Common facial features include downslanting palpebral fissures with epicanthal folds, a slightly bulbous nose, and relative macrocephaly. Twenty-eight genes map to the deleted region, including four strong candidate genes, DRD3, ZBTB20, GAP43, and BOC, with important roles in neural and/or muscular development. Analysis of the breakpoint regions based on array data revealed directly oriented human endogenous retrovirus (HERV-H) elements of ~5 kb in size and of >95% DNA sequence identity flanking the deletion. Subsequent DNA sequencing revealed different deletion breakpoints and suggested nonallelic homologous recombination (NAHR) between HERV-H elements as a mechanism of deletion formation, analogous to HERV-I-flanked and NAHR-mediated AZFa deletions. We propose that similar HERV elements may also mediate other recurrent deletion and duplication events on a genome-wide scale. Observation of rare recurrent chromosomal events such as these deletions helps to further the understanding of mechanisms behind naturally occurring variation in the human genome and its contribution to genetic disease.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Chromosomes, Human, Pair 3
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Developmental Disabilities
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Chromosome Deletion
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Cognition Disorders
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Endogenous Retroviruses
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Muscle Hypotonia
Type of study:
Diagnostic_studies
Limits:
Adolescent
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Adult
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Child
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Child, preschool
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Female
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Humans
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Infant
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Male
Language:
En
Journal:
Hum Mutat
Journal subject:
GENETICA MEDICA
Year:
2013
Document type:
Article