Application of comparative genomics in chicken gene mapping

The NDRG4 gene is a member of the N-myc downregulated gene family which belongs to the alpha/beta hydrolase superfamily. The protein encoded by this gene is a cytoplasmic protein that may be involved in the regulation of mitogenic signalling in vascular smooth muscle cells. To map this gene in the chicken chromosome, a 6000 rads chicken-hamster radiation hybrid panel (ChickRh6) was used. primers were designed according to the published human sequence for amplification of the chicken NDRG4 gene by comparative genomics. We compared the corresponding human mRNa sequence with the predicted coding sequence of the chicken NDRG4 gene, and found that the assembled contig shared a high percentage of similarity with that of the human gene. PCR of samples from the ChickRh6 revealed the locations of the NDRG4 gene to be linked to the marker PARD6G (5 cR away) with a LOD score of 20.46. Our present results support the idea that the RH technique is indeed a powerful tool for mapping genes due to its rapidity, precision, convenience and reproducibility.