title: Relationship between Type A and B personality and debrisoquine hydroxylation capacity.
abstract: OBJECTIVE
  A person with Type A personality is an 'aggressor' compared with the rarely harried Type B. Although debrisoquine hydroxylase (CYP2D6) capacity has been associated with personality, no study has specifically investigated its association with personality Type A and B. Therefore the aim of this research was to study the impact of CYP2D6 on Type A and B personality.
  
  
  METHODS
  Type A and B personality questionnaires were administered to 48 healthy patients undergoing elective orthopaedic surgery. After obtaining informed consent, patients were genotyped for the various CYP2D6 alleles by allele-specific polymerase chain reaction. Based on the genotypes, patients were grouped as extensive metabolizer (EM)1 (normal) (CYP2D6*1/*1), EM2 (intermediate) (CYP2D6*1/*4, CYP2D6*1/*5, CYP2D6*1/*9 and CYP2D6*1/*10) and EM3 (slow) (CYP2D6*4/*10, CYP2D6*5/*10, CYP2D6*10/*10 and CYP2D6*10/*17). Chi(2) was used to determine the relationship between the groups and personality types.
  
  
  RESULTS
  The percentages of patients who were of the EM1, EM2 and EM3 groups were 20.8%, 52.1% and 27.1%, respectively. There was a significant difference (P = 0.032) between the three groups in terms of personality type, in which EM1 showed a tendency to be of personality Type A while EM2 and EM3 tended to be of personality Type B.
  
  
  CONCLUSIONS
  The study suggests that there is a relationship between CYP2D6 activity and Type A and B personality.
authors.affiliation: Department of Pharmacology, School of Medical Sciences, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia. usmpcrprob@yahoo.com
authors.forename: S H
authors.initials: SH
authors.lastname: Gan
authors.forename: R
authors.initials: R
authors.lastname: Ismail
authors.forename: W A
authors.initials: WA
authors.lastname: Wan Adnan
authors.forename: W
authors.initials: W
authors.lastname: Zulmi
authors.forename: N
authors.initials: N
authors.lastname: Kumaraswamy
authors.forename: E T
authors.initials: ET
authors.lastname: Larmie
mesh_terms: D000293:Adolescent; D000328:Adult; D019389:Cytochrome P-450 CYP2D6 / Q000378:metabolism*; D004247:DNA / Q000032:analysis; D005260:Female; D005838:Genotype; D006801:Humans; D006900:Hydroxylation; D008297:Male; D008875:Middle Aged; D010551:Personality / Q000502:physiology*; D014434:Type A Personality
chemical_list: D004247:DNA; D019389:Cytochrome P-450 CYP2D6