摘要:

18 albinos were born on Lençóis island. Since 3 of them died and 5 emigrated, the prevalence of albinism is about 3% in the island. 2 inbred brothers with brachydactyly of the index fingers and 1 case of ‘achondroplasia’ were also found. The analysis of the population structure of the island suggests that its high frequency of albinism may have been produced by random drift. The index of isolation of its present population is roughly 17–27. Genealogical, clinical and histological data are presented and analyzed. Natural selection is not acting against the albinism gene at a measurable rate. Cytogenetic investigations among albinos and normals did not reveal any difference as regards frequency of aneuploidy, association of acrocentrics and chromatid gaps. The role of random processes in evolution is mentioned and the possibility that they may be more important than it is sometimes assumed is s

ISSN:0001-5652    

DOI:10.1159/000152991

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

A pair of chimeric twins, T.S. (male) and M.R. (female) first examined in 1970 are reinvestigated in order to determine if the proportions of admixture of red cells in their blood are unchanged, and if erythrocytes and leukocytes show the same percentage of admixture. T.S., M.R. and their family are investigated for HLA, serum types, and erythrocyte antigens and enzymes. A quantitative determination of ‘foreign’ cell populations in the blood of each twin is attempted for the systems ABO, and HLA, and for sex chromosomes in PHA stimulated lymphocytes. The results for the ABO system obtained by agglutination technique and by a double-layer immunofluorescence technique indicate that the population of M.R. erythrocytes in T.S. has decreased during the 7-year period, and is now below half the size found in 1970. Erythrocytes and leukocytes show the same percentage of admixture in both tw

ISSN:0001-5652    

DOI:10.1159/000152992

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

Mitochondrial malic enzyme was examined by starch-gel electrophoresis in human brain samples from 291 adults and 118 fetuses, all of European origin. Gene frequencies were estimated as MEM1 0.65 and MEM2 0.35. There was no significant difference in phenotype distribution between the sexes nor between adults and fetuses. No deviation from Hardy-Weinberg equilibrium was found. Malic enzyme was examined in various other tissues and although strongest in brain, it was also frequently active in adult testis, heart and kidney. An additional isozyme migrating less anodally than mitochondrial malic enzyme and especially prominent in heart muscle was found to be attributable to a combination of aconitase and isocitrate dehydrogenase acting on citrate in the gel buffer.

ISSN:0001-5652    

DOI:10.1159/000152993

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

It is argued that Lewis genes are responsible for adding specificity to glycol-protein molecules after the activities of the secretor, H and ABO genes, respectively, have been expressed. This conclusion is based on the results of studies on the expression of ABO and Lewis antigens in salivas from Australian aborigines, and on biochemical results. A simple figure illustrating the antigens determined on red cells and in body secretions as a result of the action of these genes, in their correct order – secretor, H, ABO, Lewis – is presen

ISSN:0001-5652    

DOI:10.1159/000152994

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

GLO I phenotypes were determined in 1,075 unrelated West German individuals by starch gel electrophoresis. Gene frequencies were 0.4512 for GLO1 and 0.5488 for GLO2. Association studies between GLO I and Bf in 985 individuals of which Bf phenotypes were known from previous reports gave no significant evidence for close association between the two systems.

ISSN:0001-5652    

DOI:10.1159/000152995

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The distribution of the Glm (1, 2, 3, 17), G2m (23), G3m (5, 10, 11, 13, 14, 15, 21, 28) and Km (1, 2) allotypic markers has been examined in 122 unrelated Vietnamese subjects originating from all regions of Vietnam. The 13 observed phenotypes have been explained by means of 8 haplotypes: 5 ‘major’ ones (which are also known to be usual in all other reported Mongoloid populations) and 3 ‘minor’ ones. Consideration of gene frequencies allows easy integration of Vietnamese within the south-north cline of Gm haplotype distribution in East Asia, where they insert between Southern Chinese, on one hand, and Singapore as well as South Central Chinese on the other hand. The observed Km1 0.290 frequency value revealed to be of the same order of magnitude as the values reported for most other non-Thai Mon

ISSN:0001-5652    

DOI:10.1159/000152996

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

This paper attempts to evaluate the dermatoglyphic (genetical) distance between two Polish population samples in relation to the intrapopulation distance coefficients estimated within each sample. All the coefficients have been based, in turn, on frequencies of fingertip, palmar and sole pattern elements, separately and for all characters combined.The results of a comparison of various combinations of dermatoglyphic characters with one another in respect of all successive values of a distance coefficient indicate that, if populations of mostly related individuals were compared, sole patterns have been the most efficient ones in differentiating between the two normal population samples. The values of inter- and intrapopulation distance coefficients obtained from samples consisting mostly of family units have been compared with those estimated in samples of non-related individuals. The limitations and difficulties in the interpretation of the values of a distance coefficient related both to the material used and statistical procedures are discussed.

ISSN:0001-5652    

DOI:10.1159/000152997

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The dermatoglyphic (genetical) distance coefficients have been estimated within monozygotic and dizygotic twin pairs, between left and right sides of the same individual and between normal subjects and 21-trisomics. All the coefficients have been based, in turn, on frequencies of fingertip, palmar and sole pattern elements, separately and for all characters combined. Quantitative variables (pattern intensities) have also been used for independent evaluation of the C2H distance coefficient in monozygotic and dizygotic twins, and in 21-trisomics as compared with normal individuals. The values of a distance have then been considered in relation to the degree of genetical likeness between the compared items as well as to the relative contribution of each pattern combination to the overall value of a distance. Some limitations in the interpretation of the results, connected mainly with statistical procedures, are also discussed.

ISSN:0001-5652    

DOI:10.1159/000153001

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

The results of Pi typing on 500 infants from Central and Southern Italy are reported. Phenotype determinations were performed on umbilical cord serum. We observed nine different phenotypes; each of these is present in other European populations. The frequencies of the Pi alleles in our group were found to be, on the whole, comparable to those found in other populations widely separated geographically. However, the frequency of the Pi S gene in our sample (0.0670) was greater than that observed in Northern and Central European and American groups. Our Pi S frequency was similar to that found in a French group and lower than that of Spanisch and Portuguese groups. Our data thus confirm the higher Pi S gene frequency in Latin populations.

ISSN:0001-5652    

DOI:10.1159/000153002

出版商:S. Karger AG    

年代:1978

数据来源: Karger

摘要:

A group of 202 unrelated Italians were screened for α1-antitrypsin using agarose-acrylamide electrophoresis and isoelectric focusing. The S and F gene frequencies were comparable to those found among Greeks and North European populations, but they differed considerably from the frequencies found among Spaniards and Portuguese. The other gene frequencies appeared to be comparable to other populations studied

ISSN:0001-5652    

DOI:10.1159/000153003

出版商:S. Karger AG    

年代:1978

数据来源: Karger