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Morphological characteristics, blood groups and blood protein polymorphisms of indigenous chickens in Bangladesh were investigated. Gene frequencies were analyzed at 29 loci controlling comb shape (the P, R and Cr loci), plumage color (the B, E, I and S loci), shank color (the Id locus), blood groups (the Ea-A, Ea-B, Ea-D and Ea-E loci) and blood proteins (the Amy-1 and-3, Akp and Akp-2, Es-1, Alb, Tf, Pas, Hb-1 and-2, LDH, 6-PGD, PGM, PHI, To, MDH and Es-D loci). In addition, phenotypic frequency of earlobe color was also examined. Among these 29 loci, 8 blood protein loci were monomorphic. Gene frequencies were compared among the local populations in Bangladesh. The frequencies of the E and I alleles for plumage color and of the Amy-lA and Hb-lA alleles for blood proteins showed a geographical cline. These frequencies were a little higher in the populations of the Chittagong Division than in those of the Dhaka Division. Although gene frequencies at other loci also varied considerably among the local populations, no geographical cline was found. Genetic distances between each pair of the local populations were small, and the coefficient of gene differentiation among them, GST, was only .058. These results suggest that the indigenous chickens (nondescript deshi type) of Bangladesh may be regarded as one breed or population.

The phylogenetic relationships among 23 local sheep breeds and varieties in East Asia were determined based on allele frequency data for five informative and polymorphic blood protein and nonprotein loci (transferrin, arylesterase, hemoglobin-beta, X-protein, and potassium transport) using electrophoresis and ion-densitometric techniques. Comparatively striking differences in the frequency distributions, especially of hemoglobin-beta and X-protein alleles, were seen between the northern population of the Khalkhas, Bhyanglung, Baruwal, Jakar, Sakten, and five Chinese breeds and the southern population of the Bengal, Kagi, Lampuchhre, Myanmar, and Sipsu breeds. Clustering analyses using UPGMA and NJ methods and principal component analysis, using the data of all populations and loci tested, clearly demonstrated the difference. The two population groups are divided by the boundary of the Himalayas, and each diverged into three subgroups: Mongolian, Tibetan, and Himalayan groups in the north and Indian groups I, II, and III in the south. It was noted that the genetic differentiation of populations was more distinct in the northern group. These findings strongly suggest the existence of at least two large and phylogenetically different gene pools of sheep in East Asia.

Allele and genotype frequency distributions of prion protein (PrP) polymorphisms at three codons, 136, 154, and 171, in East Asian sheep were determined by PCR-RFLP analysis using 553 animals from nine local breeds of the northern group and four local breeds of the southern group. Based on the genotype distribution, the risk score for scrapie was estimated. Among the local breeds, ARQ appeared predominantly (0.7701-1), followed by ARH and ARR. From such a biased allele distribution, it was difficult to ascertain the prevalent genetic relationships. A marked difference in allele frequencies between the northern and southern groups was seen (P < 0.0001). The East Asian sheep had ARQ at the highest frequency (0.8834); in European sheep it was 0.5317. According to an assessment of scrapie risk in the PrP genotype classes, the predominant ARQ/ARQ in East Asian sheep corresponded to the risk score of R4. This finding suggests that East Asian sheep have a high level of genetic susceptibility to scrapie.