UK, Ireland / What is it with black culture in the UK? [22]

This low variant MAO-A gene varies amongst groups.

"Boys who carry a particular variation of the gene Monoamine oxidase A (MAOA), sometimes called the "warrior gene," are more likely not only to join gangs but also to be among the most violent members and to use weapons, according to a new study from The Florida State University that is the first to confirm an MAOA link specifically to gangs and guns."

sciencedaily.com/releases/2009/06/090605123237.htm

UK, Ireland / What is it with black culture in the UK? [22]

These racial crime trends are consistent across the world. Testosterone for instance explains part of the difference in men committing more crime than women.

East Asians (Chinese, Japanese ancestry) have lower testosterone levels on average than whites, who have lower levels than blacks. East Asians also have lower crime rates in the UK, US and other western countries than whites, who have lower crime rates than blacks.

ncbi.nlm.nih.gov/pubmed/3455741

Another factor may be low activity variant of MAO-A which can put someone at greater risk of aggressive behaviour - this varies in frequency amongst ethnic groups.

Another factor sometimes cited is cognitive ability, for instance low iq puts someone at greater risk failing at school and dropping out. They are then more at risk of joining gangs etc. Groups differ in average iq. This is probably due to both genetic and environmental factors. gnxp.com/blog/2007/10/james-watson-tells-inconvenient-truth_296.php

psychology.uwo.ca/faculty/rushtonpdfs/P&E%20Crime.pdf - (worldwide crime figures)