Gene expression of acetylcholinesterase in hybrid catfish (Clarias gariepinus X Clarias macrocephalus) exposed to chlorpyrifos and carbaryl.

After serving as an eurotransmitter, acetylcholine is hydrolyzed by acetylcholinesterase (AChE). Inhibition of AChE is considered to be a specific biomarker for exposure to organophosphate and carbamate insecticides. In this study the AChE gene was isolated from hybrid catfish brain by RT-PCR methods using degenerate primers.

Isolation and physical mapping of sex-linked AFLP markers in nile tilapia (Oreochromis niloticus L.).

Gynogenetically produced XX and YY Nile tilapia (Oreochromis niloticus) and diploid control groups were screened for amplified fragment length polymorphisms (AFLPs) to search for sex-linked or sex-specific markers. Family-level bulked segregant analysis (XX and YY gynogenetic family pools) and individual screening (XX and YY gynogenetics and XX and XY control individuals) identified 3 Y-linked (OniY425, OniY382, OniY227) and one X-linked (OniX420) AFLP markers. OniX420 and OniY425 were shown to be allelic.