M-R - Page 2 Dr. Gina Leisching Brain & Mental Health Genes MAOA MAOA is an enzyme involved in the processing of neurotransmitters, it is sometimes called the "warrior" gene due to proposed links with aggression. Gastrointestinal Genes PEMT PEMT is an enzyme which generates phosphatidylcholine, a key component of cell membranes. Brain & Mental Health Genes MAOB MAOB is an enzyme involved in the processing of neurotransmitters, it's importance relative to MAOA is under debate. Longevity Genes NAF1 NAF1 is a key component of the telomerase enzyme. Sleep Genes MTNR1B MTNR1B is a receptor for melatonin, one of the key sleep hormones. Heart Health Genes MTHFR MTHFR is an involved in the conversion of dietary folate into a variety of key products. « 1 2