• Possible lower levels of DRD2 protein causing higher risk for drug abuse and nicotine dependence (A) [R].
  • Normal levels of DRD2 protein (GG).

The Minor "A" allele is associated with:

  • Higher rates of smoking as seen in a study of adolescents [R].
  • Increased risk of opiate addiction and required methadone treatment [R].
  • PTSD in trauma-exposed individuals [R ].

The Major "G" allele is associated with:

  • Potential greater susceptibility to Parkinsons, schizophrenia, and substance addiction (GA) [R].
  • Higher usage alcohol for adults who had lenient parents during childhood [R].

This SNP is associated with (unknown which alleles):

  • Schizophrenia in Korean populations [R].
  • Increased risk of substance addiction found in Jordanian populations. In addition, it poses a potential risk for people of Middle Eastern descent [R].


Parent Gene: DRD2

Importance: 3
Less common allele: A = 22%
More common allele: G = 78%
My Genotype: Log In