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A growing number of ancient DNA studies on Neanderthals, Denisovans and Homo sapiens suggest intertwined evolutionary and population histories, including several admixture events between early modern and archaic humans. However, ancient nuclear and mtDNA sequences revealed phylogenetic discrepancies between the three groups that are hard to explain. For example, autosomal genomes show that Neanderthals and Denisovans are sister groups that split from modern humans more than 550,000 years ago. However, all but the earliest Neanderthal mtDNA samples are far more similar to those of modern humans than to those from Denisovans. These studies suggest that Neanderthals originally carried a Denisovan-like...

Teen athletes have traditionally been classified as "boys" or "girls" so that girls can participate in sports without having to compete against boys who are usually stronger and faster than girls. This system worked as long as everyone agreed on which athletes were girls and which athletes were boys. Today some disagree about who qualifies as girls and who qualifies as boys. One thing hasn't changed. There are two different genetic types of athletes. One type has two "X" chromosomes. The other has an "XY" combination of chromosomes. Athletes who have an "XY" combination of chromosomes are usually stronger and...

The current theory on human migrations into Japan is that the original inhabitants, the Jomon people, were met about 2,500 years ago by a separate group coming mainly from the Korean Peninsula, the Yayoi people. Archaeologists have identified fewer Jomon sites from the Late Jomon Period, the era immediately before the Yayoi arrival. Global temperatures and sea levels dropped during that period, which could have made life more difficult for the hunter-gatherer Jomon people. When the Yayoi people arrived, they brought wet rice farming to Japan, which would have led to a more stable food supply for the remaining Jomon...

Modern Y-Chromosome Variation Surpasses Archaic Humans by Jeffrey Tomkins, Ph.D. * The human Y-chromosome has been a sore point among secular scientists in recent years because of its many anti-evolutionary surprises. Adding to the Darwinian grief, is yet one more shocking Y-chromosome study that more clearly illustrates the boundaries of human genetic diversity. Much controversy has brewed during the past few years over the genomic sequences of what have been termed "archaic" humans. This so-called "ancient DNA" was extracted from bone fragments of "Neandertal" and "Denisovan" specimens and then sequenced, providing draft blue prints of these respective genomes.1, 2 While...

A new look at the human Y chromosome has overturned longstanding ideas about its evolutionary history. Far from being in a state of decay, the Y chromosome is the fastest-changing part of the human genome and is constantly renewing itself.

The idea that men and women are fundamentally different from each other is widely accepted. And throughout the world, this has created distinct ideas about which social and physical characteristics are necessary in each gender to maintain healthy human development. However, social revolutions throughout the last century have challenged traditional ideas about not only which traits are normal and necessary for survival, but also how humans acquire them. Thanks to a new study from researchers at Case Western Reserve University, science is continuing the charge. By studying rare families in which a daughter shares the same Y chromosome as her...

In human development, certain genes act as master switches, ensuring that we are born with similar attributes (one head, two lungs, 10 fingers) in nearly all circumstances. Such genes tend to be highly reliable and resistant to environmental factors. Related But the gene responsible for activating male development is surprisingly unstable, leaving the pathway to male sexuality fraught with inconsistency, a study finds. The SRY gene on the Y chromosome sets off the growth of male sex organs in human embryos (all of which start out essentially female). To study the gene, researchers at Case Western Reserve University looked at...

UA geneticists have discovered the oldest known genetic branch of the human Y chromosome – the hereditary factor determining male sex. The new divergent lineage, which was found in an individual who submitted his DNA to Family Tree DNA, a company specializing in DNA analysis to trace family roots, branched from the Y chromosome tree before the first appearance of anatomically modern humans in the fossil record. The results are published in the American Journal of Human Genetics. "Our analysis indicates this lineage diverged from previously known Y chromosomes about 338,000 ago, a time when anatomically modern humans had not...

Why the Y chromosome is a hotbed for evolution Mark Henderson, Science Editor The Y chromosome is often seen as the rotten corner of the human genome — a place of evolutionary decline that is slowly decaying and threatening the end of man. Reports of its imminent demise, however, have been exaggerated. Research has indicated that, far from stagnating, the male chromosome is a hotspot of evolution that is changing more quickly than any other part of humanity’s genetic code. In most mammals the sex of offspring is determined by X and Y chromosomes. Females have two Xs, males have...

Women may think of men as primitive, but new research indicates that the Y chromosome - the thing that makes a man male - is evolving far faster than the rest of the human genetic code. A new study comparing the Y chromosomes from humans and chimpanzees, our nearest living relatives, show that they are about 30 per cent different. That is far greater than the 2 per cent difference between the rest of the human genetic code and that of the chimp's, according to a study appearing online Wednesday in the journal Nature. These changes occurred in the last...

The first words ever spoken, so fable holds, were a palindrome and an introduction: “Madam, I’m Adam.” A few years ago palindromes — phrases that read the same backward as forward — turned out to be an essential protective feature of Adam’s Y, the male-determining chromosome that all living men have inherited from a single individual who lived some 60,000 years ago. Each man carries a Y from his father and an X chromosome from his mother. Women have two X chromosomes, one from each parent. The new twist in the story is the discovery that the palindrome system has...

Y chromosome study sheds light on Athapaskan migration to southwest US A large-scale genetic study of native North Americans offers new insights into the migration of a small group of Athapaskan natives from their subarctic home in northwest North America to the southwestern United States. The migration, which left no known archaeological trace, is believed to have occurred about 500 years ago. The study, led by researchers at the University of Illinois, is detailed this month in the American Journal of Physical Anthropology. It relied on a genetic analysis of the Y chromosome and so offers a window on the...

Scientists Reshape Y Chromosome Haplogroup Tree Gaining New Insights Into Human Ancestry ScienceDaily (Apr. 3, 2008) — The Y chromosome retains a remarkable record of human ancestry, since it is passed directly from father to son. In an article published in Genome Research scientists have utilized recently described genetic variations on the part of the Y chromosome that does not undergo recombination to significantly update and refine the Y chromosome haplogroup tree. Human cells contain 23 pairs of chromosomes: 22 pairs of autosomes, and one pair of sex chromosomes. Females carry a pair of X chromosomes that can swap, or...

New research has identified the first genetic evidence of Africans having lived amongst "indigenous" British people for centuries. Their descendants, living across the UK today, were unaware of their black ancestry. The University of Leicester study, funded by the Wellcome Trust and published today in the journal European Journal of Human Genetics, found that one third of men with a rare Yorkshire surname carry a rare Y chromosome type previously found only amongst people of West African origin. The researchers, led by Professor Mark Jobling, of the Department of Genetics at the University of Leicester, first spotted the rare Y...

The Vikings (or Norse) played a prominent role in Irish history but, despite this, their genetic legacy in Ireland, which may provide insights into the nature and scale of their immigration, is largely unexplored. Irish surnames, some of which are thought to have Norse roots, are paternally inherited in a similar manner to Y-chromosomes. The correspondence of Scandinavian patrilineal ancestry in a cohort of Irish men bearing surnames of putative Norse origin was examined using both slow mutating unique event polymorphisms and relatively rapidly changing short tandem repeat Y-chromosome markers. Irish and Scandinavian admixture proportions were explored for both systems...

If you know your Y-chromosome markers, enter them in the spaces provided in the drop-down menus and it will trace paternal line names and likely countries of origin. Three names popped up in my likely ancestry: Nickle (USA and Scotland), Rogers (USA) and Mahoney (USA). Here is my Place/Time Analysis: Important notes: A match close to 100% for a given time period does not necessarily mean that your paternal-line ancestor lived in that country at that time, only that the closest match in the SMGF database had a paternal-line ancestor living in that place and time. In general, the above...

PATTAYA, Thailand -- American Mimi Marks won 8,000 dollars, a crown and several other gifts by beating out contestants from around the world to win the Miss International Queen beauty contest for transvestites and transgenders here over the weekend. Blonde Marks pipped Korea's Yu Ri and Thailand's Tiptanlree Rujiranon to win the title in the beauty quest being held for the second time. Contestants from across the world took part in the contest, which selected the most beautiful woman who had been born a man. Miss International Queen organizers said the contest aims to raise awareness of issues facing transvestites...