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Biomedical subjects

S Misawa

Publications and source records attributed to S Misawa.

At least 343 records · Page 19Linked to original sources

Population genetic studies of the Philippine Negritos. III. Identification of the carbonic anhydrase-1 variant with CA1 Guam.

Investigation of blood samples from 277 Mamanwas of northeastern Mindanao, Philippines, confirmed the concentration of the variant carbonic anhydrase-1 (CA1 3N) in this group. The frequency for the variant allele was estimated at .217 +/- .017. It occurs also in the Manobos, the Mongoloid indigenous inhabitants of the same district, although the frequency is low (.019 +/- .008). Survey of samples from other Philippine populations, including the Aeta and the Ifugao of Luzon, failed to find variants. This findings suggests different origins of the Aeta and the Mamanwa, although both are usually referred to as Negritos. The Ca1 3N protein was purified by affinity chromatography using azosulfonamide and rechromatography on a DEAE-Sephadex column. The tryptic peptide pattern of CA1 3N was similar to that of CA1 Guam already reported. Furthermore, amino acid analyses of the tryptic peptides indicated that CA1 3N is characterized by the substitution 253 Gly leads to Arg, confirming the identity of this variant with CA1 Guam. The widespread occurrence of CA1 3 variants in the Western Pacific suggests that this variant was once common in an aboriginal population of this region, from which it was scattered by gene flow.

Black People↗

Liver alcohol dehydrogenase and aldehyde dehydrogenase in the Japanese: isozyme variation and its possible role in alcohol intoxication.

Forty autopsy livers from Japanese individuals were studied concerning alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) isozymes using electrophoretic and enzyme assay methods. A remarkably high frequency (85%) was found for the atypical ADH phenotype. The gene frequencies of ADH22 and ADH32 were .625 and .05, respectively. The usual ALDH phenotype showed two major isozyme bands, a faster migrating (low Km for acetaldehyde) and a slower migrating isozyme (high Km for acetaldehyde). Fifty-two percent of the specimens had an unusual phenotype of ALDH, which showed only the slower migrating isozyme. The usual phenotype was inhibited about 20%--30% by disulfiram and the unusual type up to 90%. Such a high incidence in the Japanese of the unusual phenotype, which lacks in the low Km isozyme, suggests that the initial intoxicating symptoms after alcohol drinking in these subjects might be due to delayed oxidation of acetaldehyde rather than its higher-than-normal production by typical or atypical ADH.

Alcohol Oxidoreductases↗

Population genetic studies of the Philippine Negritos. II. gm and km allotypes of three population groups.

Serum samples of the three tribal Negrito populations in the Philippine Islands (127 from Zambales, 87 from Bataan, and 93 from Agusan) were tested for Glm(1,2,3 and 17), and G3m(5,6,11,13,14,15,16, and 21), and Km(1). The GMpatterm of the Negritos is characterized by three haplotypes, Gm1,17;21, Gm1,2,17;21, and Gm1,3;5,11,13,14, which is also characteristic of Mongoloid-related populations, especially with high incidence of the latter haplotype. They also have the haplotype, Gm1,17;5,13,14, prevalent in Africa, New Guinea, and northern Australia, suggesting an ancient link between the Negritos and the New Guinean-Australian group. Two unusual samples of G3m(15) positive without G3m(16) observed in Zambales Negritos suggest the presence of Gm1,17;5,11,13,14,15 haplotype in the population. This appears to be unique to Zambales Negritos and the first such samples to be found.

Alleles↗

Population genetic studies of the Philippine Negritos. I. A pilot survey of red cell enzyme and serum protein groups.

Electrophoretic surveys of red cell enzyme and serum protein systems representing 21 genetic loci were carried out on 129 blood samples of the Negritos of Pampanga, Central Luzon, the Philippines. Nine (out of 16) red cell enzyme loci and four (out of five) serum protein loci showed polymorphic variation. Low frequencies of ACP 1A, GPTs1, ESD2, and Hp1, and a markedly high frequency of PGM12 were contrasted to those in non-Negrito Filipinos. Variant ESD phenotypes with a slowly migrating isozyme occurred in high frequency. The new allele designated as ESD3Negrito (ESD3N) had a frequency of .10 +/- .019. In AK, a variant phenotype indistinguishable from AK 2-1 was observed in 14% of the sample. In the Gc system, a fast migrating variant was discovered in high frequency which was distinct from Gc Ab and Gc J. The variant allele, denoted GcNegrito (GcN), had a frequency of .21 +/- .025. A relatively high degree of allelic diversity in the Negrito sample was also suggested by the average heterozygosity for 21 loci screened (.165), which is compared to that of the Japanese population (.140).

Black People↗