Editing Cancer (section)

=== Heredity ===
{{Main|Cancer syndrome}}
The vast majority of cancers are non-hereditary (sporadic). [[Hereditary cancer]]s are primarily caused by an inherited genetic defect. Less than 0.3% of the population are carriers of a genetic mutation that has a large effect on cancer risk and these cause less than 3–10% of cancer.<ref name=Expert09>{{cite journal |vauthors=Roukos DH |s2cid=24746283 |title=Genome-wide association studies: how predictable is a person's cancer risk? |journal=Expert Review of Anticancer Therapy |volume=9 |issue=4 |pages=389–92 |date=April 2009 |pmid=19374592 |doi=10.1586/era.09.12|doi-access=free }}</ref> Some of these [[syndrome]]s include: certain inherited mutations in the genes ''[[BRCA1]]'' and ''[[BRCA2]]'' with a more than 75% risk of breast cancer and [[ovarian cancer]],<ref name=Expert09/> and [[hereditary nonpolyposis colorectal cancer]] (HNPCC or Lynch syndrome), which is present in about 3% of people with [[colorectal cancer]],<ref name=Lancet10>{{cite journal |vauthors=Cunningham D, Atkin W, Lenz HJ, Lynch HT, Minsky B, Nordlinger B, Starling N |s2cid=25299272 |title=Colorectal cancer |journal=Lancet |volume=375 |issue=9719 |pages=1030–47 |date=March 2010 |pmid=20304247 |doi=10.1016/S0140-6736(10)60353-4}}</ref> among others.

Statistically for cancers causing most mortality, the [[relative risk]] of developing [[colorectal cancer]] when a [[first-degree relative]] (parent, sibling or child) has been diagnosed with it is about 2.<ref name="Kampman2007">{{cite journal | vauthors = Kampman E | title = A first-degree relative with colorectal cancer: what are we missing? | journal = Cancer Epidemiology, Biomarkers & Prevention | volume = 16 | issue = 1 | pages = 1–3 | date = January 2007 | pmid = 17220324 | doi = 10.1158/1055-9965.EPI-06-0984 | doi-access = free }}</ref> The corresponding relative risk is 1.5 for lung cancer,<ref name="CotéLiu2012">{{cite journal | vauthors = Coté ML, Liu M, Bonassi S, Neri M, Schwartz AG, Christiani DC, Spitz MR, Muscat JE, Rennert G, Aben KK, Andrew AS, Bencko V, Bickeböller H, Boffetta P, Brennan P, Brenner H, Duell EJ, Fabianova E, Field JK, Foretova L, Friis S, Harris CC, Holcatova I, Hong YC, Isla D, Janout V, Kiemeney LA, Kiyohara C, Lan Q, Lazarus P, Lissowska J, Le Marchand L, Mates D, Matsuo K, Mayordomo JI, McLaughlin JR, Morgenstern H, Müeller H, Orlow I, Park BJ, Pinchev M, Raji OY, Rennert HS, Rudnai P, Seow A, Stucker I, Szeszenia-Dabrowska N, Dawn Teare M, Tjønnelan A, Ugolini D, van der Heijden HF, Wichmann E, Wiencke JK, Woll PJ, Yang P, Zaridze D, Zhang ZF, Etzel CJ, Hung RJ | title = Increased risk of lung cancer in individuals with a family history of the disease: a pooled analysis from the International Lung Cancer Consortium | journal = European Journal of Cancer | volume = 48 | issue = 13 | pages = 1957–68 | date = September 2012 | pmid = 22436981 | doi = 10.1016/j.ejca.2012.01.038 | pmc = 3445438 }}</ref> and 1.9 for [[prostate cancer]].<ref name="Watkins BrunerMoore2003">{{cite journal | vauthors = Bruner DW, Moore D, Parlanti A, Dorgan J, Engstrom P | title = Relative risk of prostate cancer for men with affected relatives: systematic review and meta-analysis | journal = International Journal of Cancer | volume = 107 | issue = 5 | pages = 797–803 | date = December 2003 | pmid = 14566830 | doi = 10.1002/ijc.11466 | s2cid = 25591527 }}</ref> For breast cancer, the relative risk is 1.8 with a first-degree relative having developed it at 50 years of age or older, and 3.3 when the relative developed it when being younger than 50 years of age.<ref name="Singletary2003">{{cite journal | vauthors = Singletary SE | title = Rating the risk factors for breast cancer | journal = Annals of Surgery | volume = 237 | issue = 4 | pages = 474–482 | date = April 2003 | pmid = 12677142 | pmc = 1514477 | doi = 10.1097/01.SLA.0000059969.64262.87 }}</ref>

Taller people have an increased risk of cancer because they have more cells than shorter people. Since height is genetically determined to a large extent, taller people have a heritable increase in cancer risk.<ref>{{cite journal | vauthors = Green J, Cairns BJ, Casabonne D, Wright FL, Reeves G, Beral V | title = Height and cancer incidence in the Million Women Study: prospective cohort, and meta-analysis of prospective studies of height and total cancer risk | journal = The Lancet. Oncology | volume = 12 | issue = 8 | pages = 785–94 | date = August 2011 | pmid = 21782509 | pmc = 3148429 | doi = 10.1016/S1470-2045(11)70154-1 }}</ref>