A “Thrifty Gene” Link Between Hoarding and Obesity

The brain-derived neurotrophic factor gene (BDNF) influences synaptic development, neural transmission, plasticity, and survival in multiple neurotransmitter systems. In its one functionally important variant, a methionine (Met) or a valine (Val; associated with higher BDNF activity) molecule occupies the codon at position 66. The Met allele, occurring in about 30% of people, has been associated with various neuropsychiatric phenomena, including anxiety, decreased memory function, and smaller hippocampal volumes, whereas the Val allele has been associated with higher activity of the BDNF system and obsessive-compulsive disorder (OCD). These investigators examined hoarding behavior, the BDNF Val66Met genotype, and body-mass index (BMI) in 30…