Some people develop a problematic relationship with gambling. This can lead to gambling disorder (GD). The researchers of this study wanted to better understand the genetics involved in GD. A total of 166 people with GD and 191 people without GD (the control group) participated in a genotyping study, where their unique genetic code was profiled. The researchers found four single nucleotide polymorphisms (SNPs) for neurotrophin genes that distinguished the GD group from the control group. They also found that two haplotypes, which are groups of SNPs, distinguished the two groups. One haplotype increased the risk of GD and the other decreased the risk of GD. Finally, the location of the SNPs in genetic code could have important information related to how the SNPs functionally contribute to the development of GD.