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Human genome

Human genome

- The human genome is the complete set of nucleic acid sequence for humans(Homo sapiens), encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual mitochondria. Human genomes include both protein-coding DNA genes and noncoding DNA. 

- Difference : human individual(~0.1%), chimpanzees(~4%), 

- MicroRNA functions as a post-transcriptional regulator of gene expression. 

- Completeness of the human genome sequence : Although the human genome has been completely sequenced for all practical purposes, there are still hundreds of gaps in the sequence. A recent study noted more than 160 euchromatic gaps of which 50 gaps were closed. However, there are still numerous gaps in the heterochromatic parts of the genome which is much harder to sequence due to numerous repeats and other intractable sequence features.

 summarizes the physical organization and gene content of the human reference genome, with links to the original analysis, as published in the Ensembl database at the European Bioinformatics Institute (EBI) and Wellcome Trust Sanger Institute.

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Chromosome Length (mm) Base pairs Variations Confirmed proteins Putative proteins Pseudogenes miRNA rRNA snRNA snoRNA Misc ncRNA Links Centromere position (Mbp) Cumulative (%)
1 85 249,250,621 4,401,091 2,012 31 1,130 134 66 221 145 106 EBI 125.0 7.9
2 83 243,199,373 4,607,702 1,203 50 948 115 40 161 117 93 EBI 93.3 16.2
3 67 198,022,430 3,894,345 1,040 25 719 99 29 138 87 77 EBI 91.0 23.0
4 65 191,154,276 3,673,892 718 39 698 92 24 120 56 71 EBI 50.4 29.6
5 62 180,915,260 3,436,667 849 24 676 83 25 106 61 68 EBI 48.4 35.8
6 58 171,115,067 3,360,890 1,002 39 731 81 26 111 73 67 EBI 61.0 41.6
7 54 159,138,663 3,045,992 866 34 803 90 24 90 76 70 EBI 59.9 47.1
8 50 146,364,022 2,890,692 659 39 568 80 28 86 52 42 EBI 45.6 52.0
9 48 141,213,431 2,581,827 785 15 714 69 19 66 51 55 EBI 49.0 56.3
10 46 135,534,747 2,609,802 745 18 500 64 32 87 56 56 EBI 40.2 60.9
11 46 135,006,516 2,607,254 1,258 48 775 63 24 74 76 53 EBI 53.7 65.4
12 45 133,851,895 2,482,194 1,003 47 582 72 27 106 62 69 EBI 35.8 70.0
13 39 115,169,878 1,814,242 318 8 323 42 16 45 34 36 EBI 17.9 73.4
14 36 107,349,540 1,712,799 601 50 472 92 10 65 97 46 EBI 17.6 76.4
15 35 102,531,392 1,577,346 562 43 473 78 13 63 136 39 EBI 19.0 79.3
16 31 90,354,753 1,747,136 805 65 429 52 32 53 58 34 EBI 36.6 82.0
17 28 81,195,210 1,491,841 1,158 44 300 61 15 80 71 46 EBI 24.0 84.8
18 27 78,077,248 1,448,602 268 20 59 32 13 51 36 25 EBI 17.2 87.4
19 20 59,128,983 1,171,356 1,399 26 181 110 13 29 31 15 EBI 26.5 89.3
20 21 63,025,520 1,206,753 533 13 213 57 15 46 37 34 EBI 27.5 91.4
21 16 48,129,895 787,784 225 8 150 16 5 21 19 8 EBI 13.2 92.6
22 17 51,304,566 745,778 431 21 308 31 5 23 23 23 EBI 14.7 93.8
X 53 155,270,560 2,174,952 815 23 780 128 22 85 64 52 EBI 60.6 99.1
Y 20 59,373,566 286,812 45 8 327 15 7 17 3 2 EBI 12.5 100.0
mtDNA 0.0054 16,569 929 13 0 0 0 2 0 0 22 EBI N/A 100.0
total   3,095,693,981   19,313 738 12,859    

 

- coding seq : Protein-coding sequences represent the most widely studied and best understood component of the human genome.  About 20,000 human proteins have been annotated in databases such as Uniprot.

- Protein-coding capacity per chromosome. Protein-coding genes are distributed unevenly across the chromosomes, ranging from a few dozen to more than 2000, with an especially high gene density within chromosomes 19, 11, and 1

 

- non-coding DNA : Noncoding DNA is defined as all of the DNA sequences within a genome that are not found within protein-coding exons, and so are never represented within the amino acid sequence of expressed proteins. By this definition, more than 98% of the human genomes is composed of ncDNA.

 

https://en.wikipedia.org/wiki/Human_genome

https://www.genome.gov/

http://web.ornl.gov/sci/techresources/Human_Genome/project/info.shtml