What is the difference between y and x chromosomes

X Chromosome: X chromosome contains more genes about genes than the Y chromosome. Y Chromosome: Y chromosome contains fewer genes about 70 genes than the X chromosome. X Chromosome: Female contains the XX genotype.

Y Chromosome: Male contains the XY genotype. Y Chromosome: Y chromosome contains the SYR gene, which is involved in the development of the testes. X chromosome and Y chromosome are the two sex determining chromosomes in the human genome. In females, two X chromosomes can be found. In males, both X and Y chromosome can be identified.

The main difference between X and Y chromosome is their involvement of sex determination in humans. One of the two X chromosomes in females is randomly and permanently inactivated by DNA methylation. The SYR gene in the Y chromosome is involved in the development of the fetus into a male. Both X and Y chromosomes contain pseudochromosomal regions, which consist of genes for the normal development of the individual.

The pseudochromosomal regions of the X and Y chromosome are homologous. National Library of Medicine. National Institutes of Health, n. Available here. Hindawi Publishing Corporation, Butler, Syed K. Rafi, Ann M. The Xp22 region includes a gene called HCCS , which carries instructions for producing an enzyme called holocytochrome c-type synthase. This enzyme helps produce a molecule called cytochrome c. Cytochrome c is involved in a process called oxidative phosphorylation, by which mitochondria generate adenosine triphosphate ATP , the cell's main energy source.

It also plays a role in the self-destruction of cells apoptosis. A deletion of genetic material that includes the HCCS gene prevents the production of the holocytochrome c-type synthase enzyme. In females who have two X chromosomes , some cells produce a normal amount of the enzyme and other cells produce none. The resulting overall reduction in the amount of this enzyme leads to the signs and symptoms of microphthalmia with linear skin defects syndrome.

In males who have only one X chromosome , a deletion that includes the HCCS gene results in a total loss of the holocytochrome c-type synthase enzyme.

A lack of this enzyme appears to be lethal very early in development, so almost no males are born with microphthalmia with linear skin defects syndrome. A few affected individuals with male appearance who have two X chromosomes have been identified.

A reduced amount of the holocytochrome c-type synthase enzyme can damage cells by impairing their ability to generate energy. In addition, without the holocytochrome c-type synthase enzyme, the damaged cells may not be able to undergo apoptosis. These cells may instead die in a process called necrosis that causes inflammation and damages neighboring cells. During early development this spreading cell damage may lead to the eye and skin abnormalities characteristic of microphthalmia with linear skin defects syndrome.

Triple X syndrome also called 47,XXX or trisomy X results from an extra copy of the X chromosome in each of a female's cells. Females with triple X syndrome have three X chromosomes, for a total of 47 chromosomes per cell. An extra copy of the X chromosome can be associated with tall stature, developmental delays, learning problems, and other features in some girls and women.

Some females with triple X syndrome have an extra X chromosome in only some of their cells. As the number of extra sex chromosomes increases, so does the risk of learning problems, intellectual disability, birth defects, and other health issues. Turner syndrome results when one normal X chromosome is present in a female's cells and the other sex chromosome is missing or structurally altered.

The missing genetic material affects development before and after birth, leading to short stature, ovarian malfunction, and other features of Turner syndrome. About half of individuals with Turner syndrome have monosomy X 45,X , which means each cell in an individual's body has only one copy of the X chromosome instead of the usual two sex chromosomes.

Turner syndrome can also occur if one of the sex chromosomes is partially missing or rearranged rather than completely absent. Some women with Turner syndrome have a chromosomal change in only some of their cells, which is known as mosaicism. Some cells have the usual two sex chromosomes either two X chromosomes or one X chromosome and one Y chromosome , and other cells have only one copy of the X chromosome.

Researchers have not determined which genes on the X chromosome are responsible for most of the features of Turner syndrome. They have, however, identified one gene called SHOX that is important for bone development and growth. The SHOX gene is located in the pseudoautosomal regions of the sex chromosomes. Missing one copy of this gene likely causes short stature and skeletal abnormalities in women with Turner syndrome.

Duplication of a small amount of genetic material on the X chromosome causes X-linked acrogigantism X-LAG , which is characterized by abnormally fast growth beginning in infancy or early childhood. Affected individuals may have the condition as a result of enlargement hyperplasia of the pituitary gland or development of a noncancerous tumor in the gland called a pituitary adenoma.

The pituitary is a small gland at the base of the brain that produces hormones that control many important body functions, including growth hormone, which helps direct growth of the body. The abnormal gland releases more growth hormone than normal, causing rapid growth in individuals with X-LAG. The duplication, often referred to as an Xq The GPR gene provides instructions for making a protein whose function is unknown, although it is thought to be involved in the growth of cells in the pituitary gland or in the release of growth hormone from the gland.

It is unclear how extra GPR protein results in the development of a pituitary adenoma or hyperplasia or in the release of excess growth hormone. Chromosomal conditions involving the sex chromosomes often affect sex determination whether a person has the sexual characteristics of a male or a female , sexual development, and the ability to have biological children fertility. The signs and symptoms of these conditions vary widely and range from mild to severe.

They can be caused by missing or extra copies of the sex chromosomes or by structural changes in the chromosomes. Genetics Home Reference has merged with MedlinePlus.

Learn more. The information on this site should not be used as a substitute for professional medical care or advice. Contact a health care provider if you have questions about your health.

X chromosome. From Genetics Home Reference. Description The X chromosome is one of the two sex chromosomes in humans the other is the Y chromosome.

Health Conditions Related to Chromosomal Changes The following chromosomal conditions are associated with changes in the structure or number of copies of x chromosome. More About This Health Condition. Intestinal pseudo-obstruction Intestinal pseudo-obstruction, a condition characterized by impairment of the coordinated waves of muscle contractions that move food through the digestive tract peristalsis , can be caused by genetic changes involving the X chromosome.

Both authors crucially revised the manuscript for important intellectual content and approved the final version to be published. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

We thank the funding agencies for supporting our study. We would also like to thank all present and former lab members for helpful discussions. Agarwal, A. Characterizing semen parameters and their association with reactive oxygen species in infertile men.

Ainsworth, C. The electrophoretic separation of spermatozoa: an analysis of genotype, surface carbohydrate composition and potential for capacitation. Aitken, R. Age, the environment and our reproductive future: bonking baby boomers and the future of sex. Reproduction , S1—S Alminana, C. The battle of the sexes starts in the oviduct: modulation of oviductal transcriptome by X and Y-bearing spermatozoa. BMC Genomics Alvarez-Uria, G.

Prevalence and severity of anaemia stratified by age and gender in rural India. Anemia Anway, M. Epigenetic transgenerational actions of endocrine disruptors and male fertility. Science , — Aranha, I. Mouse chromosome 6 in Rb translocations: consequences in singly and doubly heterozygous males. Cell Genet. Bader, G. Functional genomics and proteomics: charting a multidimensional map of the yeast cell. Trends Cell Biol.

Barazani, Y. Lifestyle, environment, and male reproductive health. North Am. Battistone, M. Bean, B. Progenitive sex ratio among functioning sperm cells. Google Scholar. Benet, J. Cytogenetic studies in motile sperm from normal men. PubMed Abstract Google Scholar. Bennett, D. Sex ratio in progeny of mice inseminated with sperm treated with H-Y antiserum. Nature , — Bermejo-Alvarez, P. Sex determines the expression level of one third of the actively expressed genes in bovine blastocysts.

Bibbins, P. Fluorescent body distribution in spermatozoa in the male with exclusively female offspring. Blomqvist, S. Epididymal expression of the forkhead transcription factor Foxi1 is required for male fertility. EMBO J. Blottner, S. Enrichment of bovine X and Y spermatozoa by free-flow electrophoresis. A 41, — Bonduelle, M. Prenatal testing in ICSI pregnancies: incidence of chromosomal anomalies in karyotypes and relation to sperm parameters.

Bonefeld-Jorgensen, E. Effect of highly bioaccumulated polychlorinated biphenyl congeners on estrogen and androgen receptor activity. Toxicology , — Brandriff, B. II, and Gledhill, B. Sex chromosome ratios determined by karyotypic analysis in albumin-isolated human sperm. Braun, R.

Genetically haploid spermatids are phenotypically diploid. Carvalho, J. Nanoscale differences in the shape and size of X and Y chromosome-bearing bovine sperm heads assessed by atomic force microscopy.

PLoS One 8:e Chandler, J. Sex ratio variation between ejaculates within sire evaluated by polymerase chain reaction, calving, and farrowing records. Dairy Sci. Chang, M. Fertilizing capacity of spermatozoa deposited into the fallopian tubes. Chaudhary, I. Sperm sex ratio X: Y ratio and its variations.

Austin J. Chayko, C. The murine Rb 6. Check, J. Male sex preselection: swim-up technique and insemination of women after ovulation induction. Chen, X. Identification and characterization of genes differentially expressed in X and Y sperm using suppression subtractive hybridization and cDNA microarray. Identification of differentially expressed proteins between bull X and Y spermatozoa.

Proteomics 77, 59— Chevret, E. Meiotic segregation of the X and Y chromosomes and chromosome 1 analyzed by three-color FISH in human interphase spermatozoa. Clapham, D. Sperm BerserKers. Colaco, S. Genetics of the human Y chromosome and its association with male infertility. Cui, K. Size differences between human X and Y spermatozoa and prefertilization diagnosis. X larger than Y.

Curtsinger, J. A two-generation study of human sex-ratio variation. De Canio, M. Differential protein profile in sexed bovine semen: shotgun proteomics investigation. Diasio, R. Effects of pH on the migration of X and Y sperm. Dominko, T. Relationship between the maturational state of oocytes at the time of insemination and sex ratio of subsequent early bovine embryos. Theriogenology 47, — Egozcue, J. Chromosome studies in human sperm nuclei using fluorescence in-situ hybridization FISH.

Update 3, — Eisenberg, M. Sperm counts and sperm sex ratio in male infertility patients. Asian J. Engelmann, U. Separation of human X and Y spermatozoa by free-flow electrophoresis. Gamete Res. Erickson, J. The secondary sex ratio in the United States association with race, parental ages, birth order, paternal education and legitimacy. Ericsson, R. Isolation of fractions rich in human Y sperm.

Evans, J. An attempt to separate fractions rich in human Y sperm. Flaherty, S. Application of modern molecular techniques to evaluate sperm sex selection methods. Garry, V. Birth defects, season of conception, and sex of children born to pesticide applicators living in the Red River Valley of Minnesota, USA.

Health Perspect. Gellatly, C. Trends in population sex ratios may be explained by changes in the frequencies of polymorphic alleles of a sex ratio gene. Geraedts, J. X spermatozoa larger than Y in Gharagozloo, P. The role of sperm oxidative stress in male infertility and the significance of oral antioxidant therapy.

Goldman, A. Analysis of the primary sex ratio, sex chromosome aneuploidy and diploidy in human sperm using dual-colour fluorescence in situ hybridisation. Grant, V. Entrenched misinformation about X and Y sperm. BMJ Griffin, D. Sex ratio in normal and disomic sperm: evidence that the extra chromosome 21 preferentially segregates with the Y chromosome.

Halder, A. Analysis of meiotic segregation in human nondecondensed interphase spermatozoa by triple colour rapid direct fluorescent in situ hybridization.

Indian J. Hamamah, S. Role of the ionic environment and internal pH on sperm activity. Han, T. Detection of X- and Y-bearing human spermatozoa after motile sperm isolation by swim-up. Simultaneous detection of X- and Y-bearing human sperm by double fluorescence in situ hybridization. Hassanane, M. Simultaneous detection of X- and Y-bearing bull spermatozoa by double colour fluorescence in situ hybridization.

Hassold, T. Human aneuploidy: incidence, origin, and etiology. To err meiotically is human: the genesis of human aneuploidy. Hendricks, K. Consequences for the bovine embryo of being derived from a spermatozoon subjected to post-ejaculatory aging and heat shock: development to the blastocyst stage and sex ratio. Hendriksen, P. Do X and Y spermatozoa differ in proteins? Theriogenology 52, — Binding of anti-H-Y monoclonal antibodies to separated X and Y chromosome-bearing porcine and bovine sperm.

Comparison of detergent-solubilized membrane and soluble proteins from flow cytometrically sorted X- and Y-chromosome bearing porcine spermatozoa by high resolution 2-D electrophoresis.

Hoegerman, S. Sex chromosome abnormalities after intracytoplasmic sperm injection. Lancet Hoffmann, D. Isolation of epithelial cells from the corpus epididymidis and analysis for glycerylphosphorylcholine, sialic acid, and protein. Holt, W. The oviduct as a complex mediator of mammalian sperm function and selection. Hoppe, P. Reacting mouse sperm with monoclonal H-Y antibodies does not influence sex ratio of eggs fertilized in vitro.

Hossain, A. Lack of significant morphological differences between human X and Y spermatozoa and their precursor cells spermatids exposed to different prehybridization treatments. Hu, Y. Functional significance of the sex chromosomes during spermatogenesis. Reproduction , R—R Iizuka, R. Sexing of human sperm by discontinuous Percoll density gradient and its clinical application. Ikeda, M. Repeated in utero and lactational 2,3,7,8-tetrachlorodibenzo-p-dioxin exposure affects male gonads in offspring, leading to sex ratio changes in F2 progeny.

Sex chromosomal abnormalities and intracytoplasmic sperm injection. Irving, J. The ratio of X- and Y-bearing sperm in ejaculates of men with three or more children of the same sex. Ishihara, K. Does paternal exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin TCDD affect the sex ratio of offspring? Iwata, H. Effects of modification of in vitro fertilization techniques on the sex ratio of the resultant bovine embryos.

James, W. Parental age, parity and sex ratio in births in England and Wales, Jasin, M. Analysis of Escherichia coli beta-galactosidase expression in transgenic mice by flow cytometry of sperm. Jeulin, C. Johnson, L. A new approach to study the architectural arrangement of spermatogenic stages revealed little evidence of a partial wave along the length of human seminiferous tubules.

Sexing mammalian sperm for production of offspring: the state-of-the-art. Gender preselection in humans? Flow cytometric separation of X and Y spermatozoa for the prevention of X-linked diseases. Jurewicz, J. Lifestyle factors and sperm aneuploidy. Kaneko, S. Separation of human X- and Y-bearing sperm using free-flow electrophoresis.

B 59, — Human X- and Y-bearing sperm differ in cell surface sialic acid content. Kirley, T. Differential sensitivity to reduction of the three beta subunit disulfide bonds. Krco, C. H-Y male antigen: detection on eight-cell mouse embryos. Kruger, A. A neofunctionalized X-linked ampliconic gene family is essential for male fertility and equal sex ratio in mice.

Kwon, W. A comprehensive proteomic approach to identifying capacitation related proteins in boar spermatozoa. Diagnosis and prognosis of male infertility in mammal: the focusing of tyrosine phosphorylation and phosphotyrosine proteins.

Proteome Res. Discovery of predictive biomarkers for litter size in boar spermatozoa. Proteomics 14, — Landrum, B. Nuclear structure of human spermatozoa. Lankenau, S. The Drosophila micropia retrotransposon encodes a testis-specific antisense RNA complementary to reverse transcriptase. Leblond, C. Definition of the stages of the cycle of the seminiferous epithelium in the rat. Lechniak, D. Sperm pre-incubation prior to insemination affects the sex ratio of bovine embryos produced in vitro.

Lobel, S.