Drosophila Blm Males Show Increased Meiotic Nondisjunction
Faculty Mentor Information
Dr. Eric Stoffregen, Lewis-Clark State College
Presentation Date
7-16-2026
Abstract
In humans, Bloom syndrome, caused by a lack of functional BLM protein, manifests as short stature, skin abnormalities, a high predisposition to cancer, and reduced fertility. Previous research in Drosophila melanogaster identified Blm helicase as crucial for proper chromosome segregation during female meiosis, with Blm females showing increased meiotic nondisjunction (ndj). The role for Blm during female meiosis was shown to be necessary for proper crossover patterning. Drosophila males do not undergo meiotic crossing over, but it is not known whether Blm plays a role in suppressing meiotic ndj in males by another mechanism. Our lab assayed sex chromosome ndj in male Blm mutants and found an approximately 3-fold elevated rate of ndj compared to Blm heterozygous males. The lack of clustering among aneuploid progeny suggests the ndj events occur primarily during meiosis, although these may result from pre-meiotic chromosome damage. These findings indicate a conserved role for Blm in meiotic genome stability across sexes and highlight Drosophila as a valuable model for understanding Bloom syndrome's underlying mechanisms.
Drosophila Blm Males Show Increased Meiotic Nondisjunction
In humans, Bloom syndrome, caused by a lack of functional BLM protein, manifests as short stature, skin abnormalities, a high predisposition to cancer, and reduced fertility. Previous research in Drosophila melanogaster identified Blm helicase as crucial for proper chromosome segregation during female meiosis, with Blm females showing increased meiotic nondisjunction (ndj). The role for Blm during female meiosis was shown to be necessary for proper crossover patterning. Drosophila males do not undergo meiotic crossing over, but it is not known whether Blm plays a role in suppressing meiotic ndj in males by another mechanism. Our lab assayed sex chromosome ndj in male Blm mutants and found an approximately 3-fold elevated rate of ndj compared to Blm heterozygous males. The lack of clustering among aneuploid progeny suggests the ndj events occur primarily during meiosis, although these may result from pre-meiotic chromosome damage. These findings indicate a conserved role for Blm in meiotic genome stability across sexes and highlight Drosophila as a valuable model for understanding Bloom syndrome's underlying mechanisms.