摘要:

SummaryAncient myths of an hermaphrodite origin of man and his subsequent bisection into male and female individuals receive unexpected confirmation from the embryological evidence. The genital ridge contains the components to form either a testis or an ovary, while two sets of genital ducts are the forerunners of the male and female reproductive tracts. The presence of potentially hermaphrodite rudiments in different organisms resulted in the failure of attempts to formulate the determination of sex in terms of classical genetics. This, in turn, has led to the hypothesis that the function of the mammalian Y chromosome is to enhance the growth of the gonadal rudiment in male embryos. The hypothesis provides an explanation for the observed bilateral asymmetry of gonadal differentiation in human hermaphrodites in terms of the bilateral asymmetry of growth of human fetal gonads. The human condition can be related to the marked asymmetry of gonadal growth and differentiation in birds. The effect of temperature in the determination of sex in alligators has likewise been explained in terms of gonadal growth. The variety of sex‐determining mechanisms met with in vertebrates suggests a non‐sex‐specific effect adapted to specific biological needs. It is suggested that certain DNA sequences on the human Y chromosome act by enhancing the growth of somatic cells in the gonadal rudiment, leading to precocious differentiation of the t

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01029.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryA cDNA clone complementary to the mRNA encoding the rabbit erythrocyte specific carbonic anhydrase, CAI, has been used as probe for human CAI sequences in the analysis of DNA from panels of rodent/human somatic cell hybrids. The presence of the human CAI gene in all hybrids correlates with the presence of chromosome 8. Together with published mapping data, this assignment indicates that three CA loci are situated on chromosome 8.

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01030.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryA cosmid clone containing the entire human type II α1 collagen gene (COL2A1) was used as probe in the Southern analysis of DNA from a panel of human/hamster somatic cell hybrids containing different portions of human chromosome 12. Two of the hybrids exhibited a similar terminal deletion q14.3→qter, but one was positive for the gene while the other was negative. Therefore, the gene must reside in the region q14

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01031.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryClose linkage was demonstrated between the loci governing the polymorphisms of complement component C8 α‐γ (C8A) and β (C8B). BothC8loci were linked to the chromosome 1 marker lociPGM1andRh. The distance between the twoC8loci andPGM1appeared identical in males and females. A female/male ratio of 1.6 was observed between the twoC8loci andRh. No evidence for linkage between theC8loci andFywas found. Preliminary results of this study were presented at the Eighth International Workshop on Human Gene Mapping, Helsinki, August 1985 (Rogdeet al.19

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01032.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummarySeven phage clones containing human sequeces were picked at random from at human genomic library cloned in Charon 4A. The clones are devoid of repetitive sequences and can be used to recognize restriction fragment length polymorphisms (Federet al.1985. The chromosomal locations of the sequences defined by the seven clones have been determined by Southern blotting and DNA hybridization to DNA from human‐mouse somatic cell hybrids. The chromosomal assignment of these sequence should increase their value as genetic markers in family studie

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01033.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryThree different samples of translocations were considered in an attempt to identify those chromosomal bands preferentially involved in variant Philadelphia chromosome (PH1) translocations, and to compare them with bands preferentially broken in constitutional and sporadic translocations. The first sample included 204 cases of variant Ph1translocations with 221 identified break‐points (bp), the second consisted of 106 cases of non‐Robertsonian constitutional translocations with 213 bp identified, and the third one of 185 bp identified in sporadic translocations found occasionally in single cells of subjects with normal karyotypes and without haematological disorders.A statistical analysis demonstrated that there are some bands preferentially broken in each of the samples, and this with a high level of significance (p<0.001). The analysis of the distributions of the χ2components permitted us to identify the 12 bands preferentially involved in variant Ph1translocations and the 13 and 9 bands preferentially involved in constitutional and sporadic translocations, respectively. The comparison among the groups of preferential bp showed that the bands most involved in the three samples are different.Some theoretical problems related to the origin of the Ph1chromosome are discu

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01034.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryThe usual advice given in standard texts is to combine classes when expected numbers are too small. It is suggested that an alternative would be to use the exact values of teh mean and variance of χ2, for which algebraic expressions are provided. The reliability of the test can be improved by using √χ2instead of χ2as the test crite

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01035.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

Summary1. A study on heterogeneity of males' surnames over time and space in the island of Sardinia was carried out using data from consanguineous marriages (1800–1970) and telephone directories (1978).2. Variation of frequency of surnames over time is barely significant and 10 times lower than that over space, which is very highly singificant.3. For sufficiently frequent surnames the estimate of the Wahlund variance, calculated form χ2for heterogeneity in space, is independent of the frequency of a surname: this supplies evidence of neutrality in line with that obtained from the frequency distribution of surnames.4. The Wahlund variance,W(also called FST), decreases regularly as the average size of the area considered (number of individuals per area,N) increases. The estimate of the parameter β in the relationW = KNβcould be of interest for the study of population structure.5. A correction factor of 1/4 must be made on the surnames' variance in consideration of their haploid unisexual transmission.6. It is suggested that surnames could provide a baseline for estimating the value of Wahlund variance under random genetic drift and hence evaluating whether a gene behaves as selectively neutral.7. The distribution of the Wahlund variances obtained from two sets of gene frequency data as compared with that obtained in comparable conditions for surnames in the same areas seems to show that most genes behave as neutral, with the exception of a few, with highWvalues, which presumably have been under different selection pressures in the area exam

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01036.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

SummaryImproved laboratory methods allow one to investigate the contribution of measured allelic variability at a locus physiologically involved in determining the expression of a quantitative trait. We present statistical methods that incorporate measured genotype information into the analysis of a quantitative phenotype that allows one simultaneously to detect and estimate the effects of a measured single locus and residual polygenic effects. Likelihoods are presented for the joint distribution of the quantitative phenotype and a measured genotype that are appropriate when the data are collected as a sample of unrelated individuals or as a sample of nuclear families. Application of this method to the analysis of serum cholesterol levels and the concentration of the group specific component (Gc) are presented. The analysis of the contribution of the commonGcpolymorphism to the determination of quantitative variability in Gc using smaples of related and unrelated individuals presents, for the first time, the simultaneous estimation of the frequencies and the effects of the genotypes at a measured locus, and the contribution of residual unmeasured polygenes to phenotypic variability.

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01037.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0003-4800    

DOI:10.1111/j.1469-1809.1986.tb01038.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY