C-value: Difference between revisions

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===Human C-values===

The [[Human genome]]<ref name="IHGSC2001">{{cite journal |title=International Human Genome Sequencing Consortium. Initial sequencing and analysis of the human genome |journal=Nature |volume=409 |pages=860–921 |year=2001 |pmid=11237011 |last1=Lander |first1=ES |last2=Linton |first2=LM |last3=Birren |first3=B |last4=Nusbaum |first4=C |last5=Zody |first5=MC |last6=Baldwin |first6=J |last7=Devon |first7=K |last8=Dewar |first8=K |last9=Doyle |first9=M |last10=Fitzhugh |first10=William |last11=Funke |first11=Roel |last12=Gage |first12=Diane |last13=Harris |first13=Katrina |last14=Heaford |first14=Andrew |last15=Howland |first15=John |last16=Kann |first16=Lisa |last17=Lehoczky |first17=Jessica |last18=Levine |first18=Rosie |last19=McEwan |first19=Paul |last20=McKernan |first20=Kevin |last21=Meldrim |first21=James |last22=Mesirov |first22=Jill P. |last23=Miranda |first23=Cher |last24=Morris |first24=William |last25=Naylor |first25=Jerome |last26=Raymond |first26=Christina |last27=Rosetti |first27=Mark |last28=Santos |first28=Ralph |last29=Sheridan |first29=Andrew |last30=Sougnez |first30=Carrie |issue=6822 |doi=10.1038/35057062|display-authors=8 }}</ref> varies in size; however, the current estimate of the nuclear haploid size of the reference human genome<ref name=GRCh38p2>{{cite web|title=Assembly Statistics for GRCh38.p2 |url=httphttps://www.ncbi.nlm.nih.gov/projects/genome/assembly/grc/human/data |website=Genome Reference Consortium |accessdate=8 February 2015 |date=8 December 2014}}</ref> is 3,031,042,417 bp for the X gamete and 2,932,228,937 bp for the Y gamete. The X gamete and Y gamete both contain 22 autosomes whose combined lengths comprise the majority of the genome in both gametes. The X gamete contains an [[X chromosome]], while the Y gamete contains a [[Y chromosome]]. The larger size of the X chromosome is responsible for the difference in the size of the two gametes. When the gametes are combined, the XX female zygote has a size of 6,062,084,834 bp while the XY male zygote has a size 5,963,271,354 bp. However, the base pairs of the XX female zygote are distributed among 2 homologous groups of 23 heterologous chromosomes each, while the base pairs of the XY male zygote are distributed among 2 homologous groups of 22 heterologous chromosomes each plus 2 heterologous chromosomes. Although each zygote has 46 chromosomes, 23 chromosomes of the XX female zygote are heterologous while 24 chromosomes of the XY male zygote are heterologous. As a result, the C-value for the XX female zygote is 3.099361 while the C-value for the XY male zygote is 3.157877.

The human genome's GC content is about 41%.<ref name=Antonarakis>{{cite book|author1=Stylianos E. Antonarakis|authorlink1=Human Genome Sequence and Variation|title=Vogel and Motulsky’s Human Genetics: Problems and Approaches|date=2010|publisher=Springer-Verlag|___location=Berlin Heidelberg|isbn=978-3-540-37654-5|page=32|url=https://www.springer.com/cda/content/document/cda_downloaddocument/9783540376538-c1.pdf?SGWID=0-0-45-855435-p173877407|accessdate=8 February 2015}}</ref> Accounting for the autosomal, X, and Y chromosomes,<ref>{{cite web|last1=Kokocinski|first1=Felix|title=Bioinformatics work notes|url=http://blog.kokocinski.net/index.php/gc-content-of-human-chromosomes?blog=2|website=GC content of human chromosomes|accessdate=8 February 2015}}</ref> human haploid GC contents are 40.97460% for X gametes, and 41.01724% for Y gametes.