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This Article: THE X-CHROMOSOME, Y-CHROMOSOME AND MITOCHONDRIAL DNA
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TITLE: DETECTION OF DNA SINGLE-COPY SEQUENCES OF PREHISTORIC TEETH. SITE MILIEU AS A FACTOR FOR PRESERVATION OF DNA
AUTHOR: J. BURGER, S.HUMMEL AND B.HERRMANN
JOURNAL: ANNALS OF ANTHROPOLOGY 1997 Jun;55(2.:193-8
ABSTRACT: DNA-extracts from prehistoric roots of teeth were analyzed by PCR (polymerase chain reaction. to investigate microsatellite-systems. Microsatellites are tiny bits of DNA that seem to be 'carried along' as a chromosome is duplicated. At the same time a genetic sub-system called Amel A/B specific to the x/y-chromosome was investigated. The samples were collected from different burial conditions of similar age. Factors leading to limited DNA-degradation are given. For the first time reproducible Quadruplex-amplification on single-copy loci of prehistoric tissue was obtained in samples from the Lichtenstein-Cave, Kr. Osterode/Harz. Positive results are explained by low temperature in the burial site. The cold temperature within the cave preserved the DNA of the tissue samples. In addition the results show that desiccation (the drying of samples. allows DNA-preservation but cannot protect the DNA from damage due to microbial origin. Microorganisms can destroy DNA-structures completely.

KEY WORDS/PHRASES
DNA-DEGRADATION
MICROSATELLITE-SYSTEMS
PCR (POLYMERASE CHAIN REACTION.

TITLE: DIFFERENTIAL STRUCTURING OF HUMAN POPULATIONS FOR HOMOLOGOUS X AND Y MICROSATELLITE LOCI
AUTHOR: R. SCOZZARI, ET ALS
JOURNAL: AMERICAN J. OF HUMAN GENETICS 1997 SEP;61(3.:719-33
ABSTRACT: The global pattern of variation at the homologous microsatellite loci DYS413 (located on the Y-chromosome. and DXS8174 and DXS8175 (both located on the X-chromosome. was analyzed by examination of 30 world populations from four continents, accounting for more than 1,100 chromosomes per locus. The data showed discordant patterns of among- and within-population gene diversity for the Y-linked and the X-linked microsatellites. For the Y-linked polymorphism, all groups of populations displayed high FST values (the correlation between random haplotypes within subpopulations, relative to haplotypes of the total population. and showed a general trend for the haplotypes to cluster in a population-specific way. This was especially true for sub-Saharan African populations. The data also indicated that a large fraction of the variation among populations was due to the accumulation of new variants associated with the radiation process. Europeans exhibited the highest level of within-population haplotype diversity, whereas sub-Saharan Africans showed the lowest. In contrast, data for the two X-linked polymorphisms were concordant in showing lower FST values, as compared with those for DYS413, but higher within-population variances, for African versus non-African populations. Whereas the results for the X-linked loci agreed with a model of greater antiquity for the African populations, those for DYS413 showed a confounding pattern that is apparently at odds with such a model. Possible factors involved in this differential structuring for homologous X and Y microsatellite polymorphisms are discussed.

KEY WORDS/PHRASES
GENE DIVERSITY
HAPLOTYPES
HOMOLOGOUS
MICROSATELLITE LOCI
POLYMORPHISM
X-LINKED
Y-LINKED

TITLE: CHARACTERIZATION OF MITOCHONDRIAL DNA AND Y-CHROMOSOME HAPLOTYPES IN A URUGUAYAN POPULATION OF AFRICAN ANCESTRY
AUTHOR: C.M. BRAVI ET ALS
JOURNAL: HUMAN BIOLOGY 1997 OCT;69(5.:641-52
ABSTRACT: We used a set of informative mtDNA (mitochondrial DNA. and Y-chromosome-specific markers to determine the origin of maternal and paternal lineages in a sample of 41 Uruguayan black individuals. We found that 20 maternal lineages were African, 13 were Amerindian, and 5 were Caucasian. In three individuals we were unable to determine the ethnic origin of the mtDNA lineages. Of the 22 males analyzed we found 4 Y chromosomes of African origin, 5 of Caucasian origin, and 13 of undetermined ancestry. Our results suggest that mtDNA and Y-chromosome-specific DNA variants may be a useful tool in determining the level of mtDNA and Y chromosome ethnic introgression in a population of a given ethnic origin.

KEY WORDS/PHRASES
DNA VARIANTS
ETHNIC ORIGIN.
ETHNIC INTROGRESSION
mtDNA



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Table of Contents (all articles on this disk)
This Article: THE X-CHROMOSOME, Y-CHROMOSOME AND MITOCHONDRIAL DNA
For this article:
      Educational Goals and Objectives  Reference Abstracts  Test Questions  References