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Mark A Jobling

Publications and source records attributed to Mark A Jobling.

24 records · Page 2Linked to original sources
PubMed2003

Duplications of the AZFa region of the human Y chromosome are mediated by homologous recombination between HERVs and are compatible with male fertility.

Deletions of the AZFa region on the long arm of the human Y chromosome cause male infertility. Previous work has shown that this is an example of a genomic disorder, since most deletions are caused by non-allelic homologous recombination between endogenous retroviral elements (HERVs) flanking the 780 kb region. The reciprocal products of these deletion events, AZFa duplications, have not been reported to date. Here we show that duplication chromosomes exist in population samples by detecting Y-chromosomal short tandem repeat (YSTR) allele duplications within the AZFa region, and by showing that two chromosomes carrying these duplicated alleles contain a third junction-specific HERV sequence. Sequence analysis of these cases, which most likely represent independent duplication events, shows that breakpoints lie in the same region of inter-HERV sequence identity as do deletion breakpoints, and thus that the mechanism of duplication is indeed the reciprocal of deletion. Consideration of the accumulated Y-STR allele diversity between duplicated copies of the AZFa region indicates that one of the duplication chromosomes has been in the population for at least 17 generations, and therefore must be compatible with male fertility.

Base Sequence↗
PubMed2003

The human Y chromosome: an evolutionary marker comes of age.

Until recently, the Y chromosome seemed to fulfil the role of juvenile delinquent among human chromosomes--rich in junk, poor in useful attributes, reluctant to socialize with its neighbours and with an inescapable tendency to degenerate. The availability of the near-complete chromosome sequence, plus many new polymorphisms, a highly resolved phylogeny and insights into its mutation processes, now provide new avenues for investigating human evolution. Y-chromosome research is growing up.

Chromosomes, Human, Y↗
PubMed2002

Homogeneity and distinctiveness of Polish paternal lineages revealed by Y chromosome microsatellite haplotype analysis.

Different regional populations from Poland were studied in order to assess the genetic heterogeneity within Poland, investigate the genetic relationships with other European populations and provide a population-specific reference database for anthropological and forensic studies. Nine Y-chromosomal microsatellites were analysed in a total of 919 unrelated males from six regions of Poland and in 1,273 male individuals from nine other European populations. AMOVA revealed that all of the molecular variation in the Polish dataset is due to variation within populations, and no variation was detected among populations of different regions of Poland. However, in the non-Polish European dataset 9.3% ( P<0.0001) of the total variation was due to differences among populations. Consequently, differences in R(ST)-values between all possible pairs of Polish populations were not statistically significant, whereas significant differences were observed in nearly all comparisons of Polish and non-Polish European populations. Phylogenetic analyses demonstrated tight clustering of Polish populations separated from non-Polish groups. Population clustering based on Y-STR haplotypes generally correlates well with the geography and history of the region. Thus, our data are consistent with the assumption of homogeneity of present-day paternal lineages within Poland and their distinctiveness from other parts of Europe, at least in respect to their Y-STR haplotypes. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00439-002-0728-0.

Alleles↗
PubMed2002

High resolution Y chromosome typing: 19 STRs amplified in three multiplex reactions.

Nineteen Y-specific short tandem repeat (STR) loci have been amplified in 768 samples from the Iberian Peninsula in order to evaluate their usefulness in forensic casework. Two previously published multiplex reactions by Thomas et al. [Hum. Genet. 6 (1999) 577] (MS1, modified here: DYS19, DYS388, DYS390, DYS391, DYS392 and DYS393) and by Ayub et al. [Nucl. Acids Res. 28 (2000) e8] (CTS: DYS434, DYS435, DYS436, DYS437, DYS438 and DYS439) plus a novel one reported here (EBF: DYS385, DYS389, DYS460, DYS461, DYS462 and amelogenin) have been used. DYS385, DYS439 and DYS391 were the most informative loci with allele diversities of 0.7997, 0.6683 and 0.5940, respectively. A total of 635 different haplotypes were observed, of which 573 (90.24%) were found in single individuals. The overall haplotype diversity was 0.9988 and that obtained by each multiplex system was 0.9812 for EBF, 0.9292 for MS1 and 0.9089 for CTS.

Base Sequence↗
PubMed2002

Y chromosomal evidence for the origins of oceanic-speaking peoples.

A number of alternative hypotheses seek to explain the origins of the three groups of Pacific populations-Melanesians, Micronesians, and Polynesians-who speak languages belonging to the Oceanic subfamily of Austronesian languages. To test these various hypotheses at the genetic level, we assayed diversity within the nonrecombining portion of the Y chromosome, which contains within it a relatively simple record of the human past and represents the most informative haplotypic system in the human genome. High-resolution haplotypes combining binary, microsatellite, and minisatellite markers were generated for 390 Y chromosomes from 17 Austronesian-speaking populations in southeast Asia and the Pacific. Nineteen paternal lineages were defined and a Bayesian analysis of coalescent simulations was performed upon the microsatellite diversity within lineages to provide a temporal aspect to their geographical distribution. The ages and distributions of these lineages provide little support for the dominant archeo-linguistic model of the origins of Oceanic populations that suggests that these peoples represent the Eastern fringe of an agriculturally driven expansion initiated in southeast China and Taiwan. Rather, most Micronesian and Polynesian Y chromosomes appear to originate from different source populations within Melanesia and Eastern Indonesia. The Polynesian outlier, Kapingamarangi, is demonstrated to be an admixed Micronesian/Polynesian population. Furthermore, it is demonstrated that a geographical rather than linguistic classification of Oceanic populations best accounts for their extant Y chromosomal diversity.

Emigration and Immigration↗