Editing Conduct disorder (section)

===Intra-individual factors===
Aside from findings related to neurological and neurochemical profiles of youth with conduct disorder, intraindividual factors such as genetics may also be relevant. Having a sibling or parent with conduct disorder increases the likelihood of having the disorder, with a heritability rate of .53.<ref>{{cite journal |author1=Gelhorn H. L. |author2=Stallings M. C. |author3=Young S. E. |author4=Corley R. P. |author5=Rhee S. H. |author6=Hewitt J. K. | year = 2005 | title = Genetic and environmental influences on conduct disorder: Symptom, domain, and full-scale analyses | journal = Journal of Child Psychology and Psychiatry | volume = 46 | issue = 6| pages = 580–591 | doi=10.1111/j.1469-7610.2004.00373.x|pmid=15877764 }}</ref> There also tends to be a stronger genetic link for individuals with childhood-onset compared to adolescent onset.<ref>{{cite journal |author1=Burt S. |author2=Truger R. |author3=McGue M. |author4=Iacono W. | year = 2001 | title = Sources of covariation among attention deficit/hyperactivity disorder, oppositional defiant disorder, and conduct disorder: The importance of shared environment | journal = Journal of Abnormal Psychology | volume = 110 | issue = 4| pages = 516–525 | doi=10.1037/0021-843x.110.4.516|pmid=11727941 }}</ref> In addition, youth with conduct disorder also exhibit polymorphism in the monoamine oxidase A gene,<ref>{{cite journal |author1=Foley D. L. |author2=Eaves L. J. |author3=Wormley B. |author4=Silberg J. L. |author5=Maes H. H. |author6=Kuhn J. |author7=Riley B. | year = 2004 | title = Childhood adversity, monoamine oxidase A genotype, and risk for conduct disorder | journal = Archives of General Psychiatry | volume = 61 | issue = 7| pages = 738–744 | doi=10.1001/archpsyc.61.7.738|pmid=15237086 |doi-access= }}</ref> low resting heart rates,<ref>{{cite journal |author1=Baker L. A. |author2=Tuvblad C. |author3=Reynolds C. |author4=Zheng M. |author5=Lozano D. I. |author6=Raine A. | year = 2009 | title = Resting heart rate and the development of antisocial behaviour from age 9 to 14: genetic and environmental influences | journal = Development and Psychopathology | volume = 21 | issue = 3| pages = 939–960 | doi=10.1017/s0954579409000509|pmid=19583891 |pmc=2756992 }}</ref> and increased testosterone.<ref>Coie, J. & Dodge, K. (1998). Aggression and antisocial behavior. In W. Damon (Series Ed.) & N. Eisenberg (Vol. Ed.), ''Handbook of child psychology: Vol.2. Social, emotional, and personality development'' (5th ed., pp.779-862). New York: Wiley.</ref>