The integrations of HK2 within RASGRF2 is strongly associated with addiction
CNN: https://edition.cnn.com/2018/09/25/health/retrovirus-addiction-study-intl/index.html
El Pais: https://elpais.com/elpais/2018/09/24/ciencia/1537810832_477585.html
Newsweek: https://www.newsweek.com/drug-addicts-more-likely-have-ancient-virus-their-genome-1137540
Daily Mail: https://www.dailymail.co.uk/health/article-6207841/Addiction-caused-ancient-virus-lingering-genomes.html
The Economist: https://www.economist.com/science-and-technology/2018/10/02/an-ancient-virus-may-promote-addiction-in-modern-people
PNAS: http://www.pnas.org/content/early/2018/09/19/1811940115