In a human gene, in average, there are 9 exons, 8 introns, exon length is around 170 bp, intron length is about 5.5 Kb.
In human chromosomes, the number of genes varies from 98 to 2,514, and the average is roughly 1000 genes per chromosome.
Chr # Total # genes Total # exons Total # introns Max # exons/gene Chromosome size (determined) Avg # of exons/gene Avg length of exon (bp) Avg length of intron Shortest exon (bp) Shortest intron (bp) Shortest gene (bp) Longest exon (bp) Longest intron (bp) Longest gene (bp) 1 2514 22345 19831 107 226828929 8.89 167.01 4736.52 2 1 78 8449 476158 980961 2 1354 12506 11152 148 238349289 9.24 163.98 5883.23 2 1 90 7572 483412 1897544 3 1394 13517 12123 118 195073306 9.7 164.06 6375.63 2 1 150 6654 497816 990999 4 926 8299 7373 85 187239983 8.96 174.78 7168.94 2 53 132 6255 494708 1467842 5 1186 9946 8760 90 177696509 8.39 189.5 7277.28 2 1 150 6574 370360 930401 6 1306 11406 10100 145 169212327 8.73 173.62 5961.61 2 31 159 7152 469892 1377570 7 2508 23045 20537 82 310210944 9.19 167.87 6703.87 2 1 14 11923 458139 1641567 8 908 7823 6915 86 143297300 8.62 171.16 7354.15 2 54 84 7308 453268 2055833 9 1033 8941 7908 72 117790386 8.66 170.66 5351.68 2 33 105 6598 276306 865661 10 1017 10273 9256 69 132016990 10.1 153.79 6412.91 2 52 105 7812 482575 1727184 11 1567 12459 10892 87 130908954 7.95 177.66 4341.42 3 1 87 6183 437543 1463302 12 1299 12399 11100 89 129826379 9.55 158.07 4570.21 2 30 81 6324 328545 1248678 13 426 3784 3358 83 95749578 8.88 183.47 7351.75 2 37 279 11555 317646 1175762 14 854 6837 6106 114 87191216 8.01 176.24 5653.7 2 51 51 11304 479079 1210740 15 843 8106 7263 104 81992482 9.62 169.79 4660.7 2 1 168 9527 207178 620362 16 1093 9986 8893 62 79932432 9.14 166.96 3661.25 2 1 75 8607 466049 1167938 17 1459 13179 11720 74 79376966 9.03 165.08 3193.16 2 30 63 4786 283762 712668 18 367 3333 2966 75 74658403 9.08 174.9 7905.4 3 67 225 4721 411175 1189866 19 1609 12169 10560 106 55878340 7.56 187.31 2032.87 2 1 81 5059 170796 298909 20 775 6492 5717 80 59424990 8.38 160.34 4403.1 3 54 135 3738 303713 1108855 21 309 2539 2230 47 33924367 8.22 168.59 5086.89 3 74 102 5916 323563 833627 22 671 5173 4502 54 34352072 7.71 171.14 3924.83 3 42 38 6762 447252 492969 X 1048 8568 7520 79 152118949 8.18 185.33 7627.85 2 54 129 6102 493512 2217347 Y 98 660 562 44 24649555 6.73 173.74 5288.54 3 67 228 2493 400349 681119 AVERAGE 1107 9741 8639 88 125737527 9 171 5539 2 31 117 7057 397200 1181571
gene length 9*170+8*5500 = 45 K
reference: Distributions of exons and introns in the human genome
Hide Comments