Centromeric alpha-satellite DNA break in reciprocal translocations
J-C Wang1, A Hajianpour, R Habibian
1Genzyme Genetics, Monrovia, CA 91016, USA.
Cytogenetic and Genome Research
|October 30, 2009
Summary
Breaks in centromeric alpha-satellite DNA were unexpectedly found in individuals undergoing genetic testing for reciprocal translocations. These breaks appear to be common and may offer insights into centromere biology.
Area of Science:
- Genetics
- Molecular Biology
- Cytogenetics
Background:
- Preimplantation genetic diagnosis (PGD) utilizes fluorescence in situ hybridization (FISH) probes.
- Balanced reciprocal translocations are a common cause of recurrent pregnancy loss and infertility.
Observation:
- Unexpected breaks in centromeric alpha-satellite DNA were identified during PGD probe selection.
- Centromere breaks were specifically investigated in individuals with reciprocal translocations near the centromere.
Findings:
- Eight centromere breaks were detected in 6 out of 11 individuals studied.
- Alpha-satellite DNA breaks were observed in multiple chromosomes (X, 1, 4, 5, 10, 11, 16, 17, 18, 19).
- Familial occurrence in 2 cases suggests mitotic and meiotic stability of derivative chromosomes.
Implications:
- Breaks in alpha-satellite DNA are not rare and occur in various chromosomes.
- These findings provide insights into centromere dynamics and biology.
- Derivative chromosomes with centromere alterations may be valuable research tools.
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