Clinal variation at aspartate aminotransferase-2 in spotted seatrout,Cynoscion nebulosus (Cuvier), inhabiting the north-western Gulf of Mexico

Clinal variation was observed at the aspartate aminotransferase-2 (AAT-2) locus in the marine fish Cynoscion nebulosus (Cuvier) inhabiting the bays and estuaries of the Texas and northern Mexico Gulf coasts. Frequency of the AAT-2(80) allele increased from 0.9% at Sabine Lake, Texas to 17.1% at Rio Soto La Marina, Mexico. A statistically significant correlation existed in the frequency of this allele with degrees north latitude and west longitude. This information, if properly incorporated into a comprehensive enhancement programme, could facilitate supplemental stocking success.