@article {8351,
	title = {Global diversity in the TAS2R38 bitter taste receptor: revisiting a classic evolutionary PROPosal.},
	journal = {Sci Rep},
	volume = {6},
	year = {2016},
	month = {2016},
	pages = {25506},
	abstract = {<p>The ability to taste phenylthiocarbamide (PTC) and 6-n-propylthiouracil (PROP) is a polymorphic trait mediated by the TAS2R38 bitter taste receptor gene. It has long been hypothesized that global genetic diversity at this locus evolved under pervasive pressures from balancing natural selection. However, recent high-resolution population genetic studies of TAS2Rs suggest that demographic events have played a critical role in the evolution of these genes. We here utilized the largest TAS2R38 database yet analyzed, consisting of 5,589 individuals from 105 populations, to examine natural selection, haplotype frequencies and linkage disequilibrium to estimate the effects of both selection and demography on contemporary patterns of variation at this locus. We found signs of an ancient balancing selection acting on this gene but no post Out-Of-Africa departures from neutrality, implying that the current observed patterns of variation can be predominantly explained by demographic, rather than selective events. In addition, we found signatures of ancient selective forces acting on different African TAS2R38 haplotypes. Collectively our results provide evidence for a relaxation of recent selective forces acting on this gene and a revised hypothesis for the origins of the present-day worldwide distribution of TAS2R38 haplotypes.</p>},
	issn = {2045-2322},
	doi = {10.1038/srep25506},
	author = {Risso, Davide S and Mezzavilla, Massimo and Pagani, Luca and Robino, Antonietta and Morini, Gabriella and Tofanelli, Sergio and Carrai, Maura and Campa, Daniele and Barale, Roberto and Caradonna, Fabio and Gasparini, Paolo and Luiselli, Donata and Wooding, Stephen and Drayna, Dennis}
}
@article {7719,
	title = {The Kalash genetic isolate: ancient divergence, drift, and selection.},
	journal = {Am J Hum Genet},
	volume = {96},
	year = {2015},
	month = {2015 May 7},
	pages = {775-83},
	abstract = {<p>The Kalash represent an enigmatic isolated population of Indo-European speakers who have been living for centuries in the Hindu Kush mountain ranges of present-day Pakistan. Previous Y chromosome and mitochondrial DNA markers provided no support for their claimed Greek descent following Alexander III of Macedon{\textquoteright}s invasion of this region, and analysis of autosomal loci provided evidence of a strong genetic bottleneck. To understand their origins and demography further, we genotyped 23 unrelated Kalash samples on the Illumina HumanOmni2.5M-8 BeadChip and sequenced one male individual at high coverage on an Illumina HiSeq 2000. Comparison with published data from ancient hunter-gatherers and European farmers showed that the Kalash share genetic drift with the Paleolithic Siberian hunter-gatherers and might represent an extremely drifted ancient northern Eurasian population that also contributed to European and Near Eastern ancestry. Since the split from other South Asian populations, the Kalash have maintained a low long-term effective population size (2,319-2,603) and experienced no detectable gene flow from their geographic neighbors in Pakistan or from other extant Eurasian populations. The mean time of divergence between the Kalash and other populations currently residing in this region was estimated to be 11,800 (95\% confidence interval = 10,600-12,600) years ago, and thus they represent present-day descendants of some of the earliest migrants into the Indian sub-continent from West Asia.</p>},
	keywords = {Asia, Asian Continental Ancestry Group, Chromosomes, Human, Y, Demography, DNA, Mitochondrial, European Continental Ancestry Group, Genetic Drift, Genetics, Population, Haplotypes, History, Ancient, Humans, Male, Pakistan, Phylogeny},
	issn = {1537-6605},
	doi = {10.1016/j.ajhg.2015.03.012},
	author = {Ayub, Qasim and Mezzavilla, Massimo and Pagani, Luca and Haber, Marc and Mohyuddin, Aisha and Khaliq, Shagufta and Mehdi, Syed Qasim and Tyler-Smith, Chris}
}
