摘要:

A number of recent genetical experiments and microbiological models are directly applicable to human ophthalmogenetics. This is particularly the case in models and experiments involving X-chromosomal markers because X-chromosomal traits are well studied in the eye. The high prevalence of colour blindness in the Western world relative to primitive people has been explained as a lessening of a selectional pressure through evolution, and the emergence of trichromatic colour vision in primates has evidently been of great selective advantage. These evolutionary new characters can be ascribed to the redundancy of colour vision loci on the X chromosome. Colour-vision abnormalities are sometimes acquired, and some linkage studies are invalidated by deficient differentiation between phenotype and genotype of colour vision. Two reports of monocular deutan colour blindness in males have, so far, remained unexplained. Chimaerism might be an acceptable explanation because mouse chimaeras have been shown to have very dissimilar proportions of the constituent genotypes in the pigment epithelium of the two eyes in each animal. The clonal number of cells at the time of X-inactivation has been calculated in women heterozygous at the G-6-PD locus, in mice, this probably occurs before the differentiation of the mesoderm from the ectoderm. In man, such estimation has not yet been done. It is suggested to use the lens of carriers of G-6-PD variants in such estimations. A theory of the development of the cornea by a centripetal spiral pattern is proposed on the basis of the morphology of affected and heterozygotes for Fabry’s disease. It is also argued that Knudsons’s theory on the origin of heritable retinoblastoma from a mean of three cells can be tried by an estimation of G-6-PD variants in tumour cells from G-6-PD heterozygotes. Compound heterozygotes are at present a much-debated subject, and a list of X-borne loci with multiple alleles, supplementing earlier listing, is provided. X-linked retinitis pigmentosa and X-linked cataract are presented as polyallelic traits. Accepting the current theory of X-inactivation, evidence can be provided that the determination of human photoreceptor cells takes place before the embryo is lateralised because in this way the wide inter- and intrafamilial variation and the irrelevant inter-ocular variation in the manifestation in carriers can be accounted for. From experiments in mice carrying an X-linked marker for albinism, the same early determination has been hypothesised for the melanoblasts in the posterior part of the

ISSN:0001-5652    

DOI:10.1159/000152699

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Two of the multiple forms of human guanylate kinase (the components e and c) described by MONN and CHRISTIANSEN could be separated from the guanylate kinase of Chinese hamster in man-Chinese hamster hybrids on cellulose acetate gel. By employing a number of enzyme markers, whose loci have been already assigned to particular human chromosomes, as main markers in man-Chinese hamster hybrids, evidence was gathered to indicate that the components e and c of GuK are determined by two separate loci situated on the human chromosome number 1 distal to the break point q 2.2.

ISSN:0001-5652    

DOI:10.1159/000152700

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

A total of 811 young people (16–27 years) of both sexes were studied in a health screening program during which multiple biochemical, haematological, and physical variables were measured. In addition, the phenotypes of these subjects were established at 22 polymoφhic gene loci. Analysis of variance by several methods showed no more statistically significant differences than would be expected by chance in any of these variables between persons of distinct phenotypes apart from those associations which have been delineated previously (e.g., cholesterol and ABO blood group, alkaline phosphatase and ABO blood group). More interesting findings were those which related the variables among themselves. Thus, weight, serum protein level, and red blood cell measurements were found to be positively correlated to a substantial extent with blood pressure readin

ISSN:0001-5652    

DOI:10.1159/000152679

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Gene frequencies at 22 polymorphic loci, including blood groups, serum proteins, and red cell enzymes, were calculated in a Dutch population of 806 individuals. 18 further loci at which little or no variation was found were also studied.

ISSN:0001-5652    

DOI:10.1159/000152680

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Chromosome analysis of 209 out of 259 children, born to mothers aged 40 years or more who were delivered in the University Clinic Rigshospitalet, Copenhagen, from 1961 to 1966, revealed 4 cases of trisomy 21, one triplo-X individual and one peri-centric inversion in a boy with 46, XY chromosome complement. 50 children could not be examined: 33 were dead, 17 unobtainable. As judged from hospital records two of the deceased children had Down’s syndrome. A minimum of 8 (3.3%) of the investigated thus had chromosome abnormalities. The perinatal mortality in the material was 12.4% compared with a perinatal mortality for older mothers of 5.5% in Denmark in the same period of tim

ISSN:0001-5652    

DOI:10.1159/000152681

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The MN blood groups have been determined in the zones of La Vera and Las Hurdes (Cáceres). Las Hurdes, with a population which has lived isolated during several centuries, show MN frequencies similar to those of the adjacent zones, such as Salamanca. New data on La Alberca, a village of the province of Salamanca, confirm the low M frequency of this province. The present findings do not modify our previous results in 3,100 tests of the population of Spain

ISSN:0001-5652    

DOI:10.1159/000152682

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The frequency of the Ag(x) antigen was determined on populations sampled from Germany (Mainz), Africa (Angola and Senegal), Bulgaria (Sofia), Australian aborigines (AWA and YO) and Greece (Athens). The gene frequencies of the Ag(x) antigen were 0.1994 (Mainz), 0.0856 (Angola), 0.1401 (Senegal), 0.2574 (Sofia), 0.4679 (AWA), 0.5343 (YO), and 0.4000 (Athens). The results are discussed.

ISSN:0001-5652    

DOI:10.1159/000152683

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

The distribution of isoenzyme variants of 6-phosphogluconate dehydrogenase, acid phosphatases, phosphoglucomutase and adenylate kinase in various African populations is reported. Gene frequencies are compared with the distribution pattern known in other African groups. The possible interpretations of these observations are discussed.

ISSN:0001-5652    

DOI:10.1159/000152684

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

Elastase and trypsin were compared for the assay of human serum α1-antitrypsin. (1) For distinguishing MM and MZ types, the combination of concentration and elastase inhibitory capacity was more accurate than the combination of concentration and trypsin inhibitory capacity. (2) Compared to type MM serum, ZZ serum was at least 50 times more deficient in elastase inhibitory capacity than in trypsin inhibitory capacity. Since excessive elastase activity may be causally related to emphysema, the demonstration that the serum of a ZZ individual may be more deficient in serum elastase inhibition than in trypsin inhibition may have pathogenetic significance

ISSN:0001-5652    

DOI:10.1159/000152685

出版商:S. Karger AG    

年代:1974

数据来源: Karger

摘要:

In order to be understandable, serologic data have to undergo a series of transformations generating more or less distorted ‘facts’ at different levels of this information processing. Some non-trivial aspects of these transformation steps and their influence on the different fact levels are discus

ISSN:0001-5652    

DOI:10.1159/000152686

出版商:S. Karger AG    

年代:1974

数据来源: Karger