Y Chromosome

The XY sex-determination system is a well-known sex-determination system. It is found in human beings and other mammals. In the XY sex-determination system, females have two of the same kind of sex chromosome (XX), while males have two distinct sex chromosomes (XY). Some species (including humans) have a gene SRY on the Y chromosome that determines maleness; others (such as the fruit fly) use the presence of two X chromosomes to determine femaleness.

SRY is not the only male-determining gene in mammals, or even the most common: most non-primate mammals use a different Y-chromosome gene, UBE1, for this purpose. Also, two species of "mole voles", Ellobius tancrei and E. lutescens, have lost the Y chromosome entirely. In one species, both sexes have unpaired X chromosomes; in the other, both females and males have XX.
See also

    * chromosome, for information on abnormalities of the XY sex-determination system
    * intersexual for information on variations in human sexual forms
    * sexual differentiation, (human)
    * testis-determining factor
    * Barr body
    * Y-chromosomal Adam

External links

    * Sex Determination and Differentiation (http://www.biology.ucsc.edu/people/barrylab/public_html/classes/old_animal_behavior/Sex_devo.htm)
    * SRY: Sex determination (http://www.ncbi.nlm.nih.gov/books/bv.fcgi?call=bv.View..ShowSection&rid=gnd.section.156) from the National Center for Biotechnology Information

Chromosome Web Watch - Resource site for researchers. Includes links to conferences and courses, directories, laboratories, journals, and publishers.
-- http://cse.nias.affrc.go.jp/shignak/chromosome.net/index2.html   Science: Biology: Genetics   (65)

The Selfish Gene - An introduction to genetics, covers the basics including cell mechanics, chromosome structure, genotypes and phenotypes, recombination, cloning and mapping.
-- http://anirvan_c.tripod.com   Science: Biology: Genetics   (65)

Chromosome Deletion Outreach, Inc. (CDO) - Non-profit voluntary support group for families affected by rare chromosome disorders.
-- http://www.chromodisorder.org/   Health: Support Groups: Conditions and Diseases: Genetic Disorders   (6)

European Chromosome 11Q Network - De groep bestaat uit ouders met kinderen met afwijkingen van chromosoom 11q.
-- http://www.11q.org/   World: Nederlands: Gezondheid: Aandoeningen en Ziekten: Genetische Stoornissen   (2)

Chromosomes and Genetic Mapping - Understanding how mapping affects the gender of a transsexual.
-- http://www.woodrow.org/teachers/bi/1994/chromosomes.html   Society: Transgendered: Health and Wellness   (1)

Genetic researchers announce big step in sequencing smallest chromosome - [CNN]
-- http://www.cnn.com/2000/HEALTH/05/08/chromo.22/index.html   News: Online Archives: CNN.com: 2000: May: Health   (3)

Europ�isches Chromosome 11q Netzwerk - Die Gruppe besteht aus Eltern, deren Kinder eine Abweichung an dem langen Arm des Chromosomes 11 haben. Sie sucht andere Eltern in Europa und anderen Teilen der Welt um, Eltern miteinander in Kontakt zu bringen, m�glichst viele Ausk�nfte �ber diese sehr seltenen Abweichungen zu sammeln und den neuesten Forschungsergebnissen zu folgen.
-- http://www.11q.org/basisdui.htm   World: Deutsch: Gesundheit: Krankheiten und Beschwerden: Genetik   (1)

What Can Our Chromosomes Tell Us? - Interactive karyotyping activity, in which you can determine if different individuals have specific genetic diseases or not.
-- http://gslc.genetics.utah.edu/units/disorders/karyotype/   Kids and Teens: School Time: Science: Living Things: Genetics   (1)

Chromosome 22 Central - A support group for families who have children affected by disorders involving chromosome 22.
-- http://www.nt.net/~a815/chr22.htm   Regional: North America: Canada: Ontario: Localities: T: Timmins: Health   (1)

Human Chromosome 19 and Mouse Comparison - Provides access to tools and data used in comparative analysis of human chromosome 19 and related DNA in mouse, as published in the July 6, 2001 issue of Science.
-- http://bahama.jgi-psf.org/pub/ch19/   Regional: North America: United States: Government: Executive Branch: Departments: Energy: DOE National Laboratories: Joint Genome Institute: Research Areas   (1)

Scientists map fourth human chromosome - [CNN]
-- http://cnn.com/2003/TECH/science/01/02/chromosome.14/index.html   News: Online Archives: CNN.com: 2003: January: Tech   (1)

Scientists sequence first human chromosome - [CNN]
-- http://www.cnn.com/1999/HEALTH/12/01/chromosome.22/index.html   News: Online Archives: CNN.com: 1999: December: Health   (1)

Boys battle rare, puzzling chromosome disorder - [CNN]
-- http://cnn.com/2004/HEALTH/01/02/sick.brothers.ap/index.html   News: Online Archives: CNN.com: 2004: January: Health   (1)

Scientists try to build a better chromosome - [CNN]
-- http://www.cnn.com/TECH/computing/9903/11/t_t/artificial.chrom/index.html   News: Online Archives: CNN.com: 1999: March: Tech   (1)

Scientists close to deciphering Y chromosome - [CNN]
-- http://www.cnn.com/2000/HEALTH/men/10/30/guy.chromosome.ap/index.html   News: Online Archives: CNN.com: 2000: October: Health   (1)

Bobb/Bopp - Creating a worldwide family tree by testing the male Y-chromosome. Includes current results, participation criteria and applicable contacts. Includes variants such as Popp, Paup, Bob, Babb, Bubb and associated spellings.
-- http://www.angelfire.com/nb/bobbdna/   Society: Genealogy: Surnames: B   (6)

The Dog Genome Project - The Dog Genome Project is a study involving the University of California, Berkeley, the University of Oregon, and the Fred Hutchinson Cancer Research Center. It is aimed at producing a map of all the chromosomes in dogs.
-- http://mendel.berkeley.edu/dog.html   Health: Animal: Conditions and Diseases: Cancer: Research   (1)

Syndrome d'Angelman - Informations sur cet accident g�n�tique orphelin sur le chromosome 15 touchant une naissance sur 20000. Par une famille de malade.
-- http://www.angelman.ch/   World: Fran�ais: Sant�: Maladies: G�n�tiques   (2)

Genetic Org - Klinfelter's support site. Designed to provide support and education for families and professionals dealing with these genetic conditions, including sex chromosome variations 47XXY, 48XXYY, 48XXXY, 49XXXXY, and 46XY/47XXY mosaic.
-- http://www.genetic.org/   Society: Transgendered: Intersexed   (4)

XXYNOY - This is a list for parents of xxy sons, or other sex chromosome anomalies. Learning and supporting each other is the goal. It is a restricted list and members must be approved by the moderator.
-- http://groups.yahoo.com/group/XXYNOY   Society: Transgendered: Family and Relationships: Mailing Lists   (2)