Question: Epigenetics as come up and we have also mentioned some twin studies in past weeks as well. But ev…

Epigenetics as come up and we have also mentioned some twin
studies in past weeks as well. But even with these considerations,
ultimately they relate to genes and our DNA. So considering nature
versus nurture, are there genes that have been discovered that are
clearly linked from a phenotypic standpoint to a behavior trait?
Please share details (location, inheritance, etc) of any gene
discoveries with us as well as your references (as always). Are
there other factors involved with this expression, like a nurture
component?