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D Carmelli

Publications and source records attributed to D Carmelli.

At least 109 records · Page 6Linked to original sources
PubMed1982

A nonparametric distance analysis of biochemical genetic data from the Aland Islands, Finland.

Biochemical genetic data from 3272 individuals from the Aland Islands, Finland, are analyzed using a recently developed set of nonparametric genetic distance measures. These measures are more robust than the traditional methods used in previous studies of this population. While there was general agreement in the results of the traditional and nonparametric approaches, some important differences were seen. In these cases, the nonparametric methods gave result more congruent with population history, geographic pripinquity, and migration patterns. Heterozygosity measures were also calculated for the Aland Islands population and compared to values obtained for Jewish populations. The total heterozygosity values were very similar.

Finland↗
PubMed1982

Contrasting patterns of familiality for cholesterol and triglyceride in Finland according to type of coronary manifestations and locations.

A descriptive genetic analysis (offspring between parent plot) was applied to serum cholesterol and triglyceride levels of 1044 Finnish subjects who were parents, siblings, spouses, and offspring of 204 male probands with angina pectoris or nonfatal myocardial infarction before age 55 years. The same analysis was also applied to 511 relatives of 106 control men matched to the probands for age and location (northeastern Finland or southern Finland). Striking differences in the plot results for triglyceride data suggest that male probands with angina pectoris as first evidence of coronary disease had different familial characteristics than those with nonfatal myocardial infarction at the onset. Further plot contrasts suggest stronger major gene effects for cholesterol and triglyceride levels in northeastern Finland, both in case and control families. Genetic makeup may help explain why men in northeastern Finland have the world's highest rate of early coronary heart disease.

Adult↗
PubMed1982

Association arrays for comparing familial total cholesterol, high density lipoprotein cholesterol, and triglyceride similarity in the Israeli population by country of origin.

The method of association arrays is applied to plasma total cholesterol, triglyceride, and high density lipoprotein cholesterol concentrations measured for 2485 young men and women aged 17-18 years and living in Jerusalem, and for their parents. These triad families are divided into five groups according to whether they were of mixed "origins." Stronger associations are present for all lipid and lipoprotein cholesterol variables in Asian and African families relative to families of other origins, possibly reflecting the more disciplined life-style patterns in these families relative to other families. Parent and offspring values exhibit positive association for all lipid variables in all groups. Patterns of familial similarity revealed by the association arrays are discussed in relation to historic and cultural differences among groups.

Adolescent↗
PubMed1982

Analysis of biochemical genetic data on Jewish populations. III. The application of individual phenotype measurements for population comparisons.

Individual phenotypic data on six blood markers and six enzyme polymorphisms in seven Jewish and two non-Jewish populations were subjected to a comparative statistical analysis. A set of functionals defined with respect to the individual biochemical profiles was used to investigate the following problems: (1) What are the distributional characteristics of various types of individual heterozygosity measures (for blood and enzyme loci) within and across populations? (2) Is the observed phenotypic variation in agreement with what might be expected if the loci were independent? (3) What proportion of the characteristics can be explained by reference to population structure and historical data? Average total heterozygosity of blood and protein loci was highest in the Iraqi population and lowest in the Yemenite. The differences among the other populations were not significant. The highest cumulative recessive homozygosity of blood markers occurs in Yemenites and Samaritans. No association was present between total blood and protein heterozygosity. Applications of these ideas and techniques to the study of multilocus genetic organization are discussed.

Blood Group Antigens↗
PubMed1981

Structured exploratory data analysis (SEDA) for determining mode of inheritance of quantitative traits. I. Simulation studies on the effect of background distributions.

We examine through simulations the effectiveness of a new methodology to help distinguish among monogenic, multifactorial, and sporadic trait transmission from parents to offspring in nuclear family data sets. The major gene index (MGI), which compares the deviation of the offspring from the midparental value with a function of the individual deviations between parents and offspring, aids in the discrimination of multifactorial from sporadic and monogenic models. In contrast with other methodologies, the ability of the MGI to separate multifactorial, monogenic, and sporadic models improves with increased skewness in the trait distribution. The midparental correlation coefficient serves as a further guide for indicating mode of inheritance. A new class of techniques, the offspring between parents function (OBP), is introduced that provides a more sensitive tool to help in assessing mode of transmission through the analysis of the level, shape, and undulation characteristics of the curves. Four data examples are used to illustrate the methodology: erythrocyte catechol-O-methyltransferase (COMT) activity, height, weight, and triglyceride measurements. Height appears largely multifactorial, and weight appears to be mostly sporadic, while COMT and triglyceride measurements suggest the presence of some major gene influences.

Genetics↗
PubMed1980

Analysis of some two-locus systems for traits exhibiting continuous variation.

Some generalized two-locus, major-gene models for traits exhibiting continuous expression are investigated. Conditions of gametic equilibria are stated as functions of the parameters characterizing the within phenotypic-genotypic distributions. Selection is stabilizing in favor of an optimum phenotype. It is established that an increase in the phenotypic variance facilitates stability of a central polymorphic state with tighter linkage. Also, with increased phenotypic variance in an additive two-locus selection model, a HARDY-WEINBERG type of equilibrium will be less central. The rate of convergence, in this case, is slowed down with an augmented environmental background.

Genetic Linkage↗
PubMed1980

The effects of increased phenotypic variance on the evolutionary outcomes of generalized major-gene models.

The study of generalized major-gene models has been extended to accommodate selective, assortative mating mechanisms. In this formulation the consequences of amplified phenotypic variance on the major gene frequency are investigated. It is shown that the rate of approach to the equilibrium state is slowed under attenuated assortative mating tendencies and/or with increased environmental noise. Also, an increased phenotypic variance induces more skewness in the nature of the gene frequencies, i.e. a less 'central' polymorphic expression. Where strong positive assortative mating occurs, a population fixation state results. Negative assortment generally facilitates the stability of a 'central' polymorphism.

Alleles↗
PubMed1979

Linkage analysis and the inheritance of arches in a Habbanite isolate.

A pedigree and linkage analysis was performed on a corrected version of the Habbanite pedigree 2 of Slatis et al. [1]. The trait "arch on any digit" was examined for major gene inheritance and possible linkage to several blood and serum group markers. The results confirm the proposed dominant major gene inheritance of this trait with almost complete penetrance. In addition, the analysis suggests linkage with the haptoglobin locus with evidence against linkage with Pl and Rhesus. These results are of particular interest in view of recently reported dermatoglyphic associations with haptoglobin.

Consanguinity↗
PubMed1979

Genetic linkage between hereditary hemochromatosis and HLA.

A large Mormon pedigree of a proband with hemochromatosis was studied, using transferrin saturation as the quantitative phenotypic trait. The analysis indicated that the inheritance of hemochromatosis was recessive, with partial expression in some heterozygotes. The lod score of 6.88 (theta = .0) was strongly indicative of linkage between the hemochromatosis locus and the human major histocompatibility (HLA) loci.

Chromosome Mapping↗
PubMed1977

Some population genetic models combining artificial and natural selection pressures in the presence of assortative mating.

We have attempted quantitatively through a series of assortative mating models to gain insight into the interaction between the usually antagonistic tendencies of artifical and natural selection pressures. We summarize some of the robust conclusions. In cases where natural selection is expressed only through the phenotype and acts in the opposite direction to the culling incline, then fixation of the dominant or recessive type can be achieved and which occurs depends critically on the initial composition of the population and the magnitude of the degree of culling compared to the selection coefficients. With traits determined at two loci in the case that the double heterozygote is the desired kind, the effect of selfing can only be overcome by very strong artificial selection pressures (high culling order). The degree of culling to achieve its objective can be relaxed with weakening of linkage. The relevant comparison is r2+(1-r)2less than 2(1-c) indicating the precise extent of culling needed, to prevent fixation. The relationships are more complex when natural selection forces are also involved (see Model IV).

Alleles↗