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Alternate-2 disjunction in the german cockroach.
1Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061.
Genetics
|May 1, 1983
Summary
This study reviews evidence for two types of alternate disjunction in German cockroach translocation heterozygotes. Unique cytomorphological features allow identification of these disjunction types, supporting alternate-2 disjunction existence.
Area of Science:
- Genetics
- Cytology
- Entomology
Background:
- Translocation heterozygotes in Blattella germanica exhibit complex chromosomal behaviors.
- Understanding alternate disjunction is crucial for studying inheritance patterns in this species.
Purpose of the Study:
- To review and present evidence for two distinct types of alternate disjunction in German cockroach translocation heterozygotes.
- To demonstrate the identifiability of these disjunction types using cytomorphological features.
Main Methods:
- Review of existing evidence on alternate disjunction in Blattella germanica.
- Cytomorphological analysis of translocation figures, specifically T(7;12)/7;12.
- Presentation of photographic evidence for alternate-1 and alternate-2 disjunction.
Main Results:
- Two types of alternate disjunction (alternate-1 and alternate-2) are supported by cytomorphological evidence.
- Unique cytomorphological features enable unambiguous identification of alternate disjunction types.
- Photographic evidence for T(7;12)/7;12 supports the proposed disjunction mechanisms.
Conclusions:
- Alternate disjunction in German cockroach translocation heterozygotes is distinguishable into two types.
- Cytomorphological analysis provides robust evidence for these disjunction patterns.
- The existence of alternate-2 disjunction is further substantiated by the presented data.
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