Tyrosine Hydroxylase (TH)
 
Variant Association Phenotype Sample Information Author
rs3842727 rs6356 Allelic:ns Genotypic:ns Haplotypic: ns Suicide attempts Etnicity: German Giegling, 2009
Cases: 111 suicide attempters, M=43; F= 68; mean age 39.2 ± 13.6
Controls: 289 subjects M=123 F=166; mean age 45.2 ± 14.9

rs3842727

rs6356

Allelic: ns
Genotypic: ns

Haplotypic: ns

Suicide and suicide attempts

Ethnicity: German

Giegling, 2007

Cases: 167 suicide attempters (M:58, F:109; mean age, 39.89 ± 13.89; 60 patients classified as violent and 101 as impulsive)

Cases: 92 Caucasian suicide completers (M:53, F:39; mean age 51.8 ± 18.5)

Controls: unrelated German volunteers without personal or family histories of neuropsychiatric disorders (F:174, M: 138; mean age, 45.01 ± 14.92)

Notes: excluded stratification using genomic control; no association with personality traits; stratified for violence, impulsiveness, and completions versus attempts

Intron 1 tetranucleotide repeat

 

Allelic: ns Suicidal behaviour severity Cases: 336 (F:62%) bipolar patients from 305 nuclear families (mean age: 35.36± 10.37 SD), including 267 patients with suicide ideas or attempts De Luca, 2007

Notes: suicidality assessed quantitatively and coded as follows: 0 = absence of suicide/death thoughts, 1 = thoughts of death, 2 = suicide ideation, 3 = suicide plan, 4 = suicide attempt; marginal association between TH & severe suicidal behaviour


Val81Met

Val468Met

Allelic: ns
Genotypic: ns

Suicide

Ethnicity: Japanese

Hattori, 2006
Cases: 189 suicide victims (F: 62, mean age ± SD, 47.9±17.6)
Controls: 187 unrelated volunteers (F:61; mean age ± SD, 44.7 ± 14.9)

Promoter locus

Genotypic: ns

Suicide attempts

Ethnicity: English, Caucasian

Ho, 2000
Cases: Bipolar (M:58, F: 73 female) and  unipolar patients (M:53, F: 86)
Notes: in the unipolar sample, the promoter locus associated with psychotic symptoms; uncorrected for multiple testing

THK 1-5

 

 

Genotypic: +, THK3, p=.0023, patients with adjustment disorders

Suicide attempts

Ethnicity: Caucasian, mostly Swedish

Persson, 1997

Cases: suicide attempters: F:76,M:42; mean age: 41

Nonpsychiatric controls: F:33,M:45; mean age: 39
Notes: Bonferroni corrected

Notes: += positive,significant; - =negative,significant; ns=nonsignificant; F=females; M=males

Dopamine Transporter (SLC6A3)
 
Variant Association Phenotype Sample Information Author

 

3’ UTR VNTR in exon 15

 

Genotypic: ns

Suicide attempts

Ethnicity: White Italian Caucasian

Gerra 2005
Heroin-dependent patients: n: 104 males (mean age:33.7±12.3 ), including 22 suicide attempters
Healthy male volunteers: n: 125 (mean age:35.7±13.9)
Notes: The 9-repeat allele confers increased susceptibility to antisocial violent behaviour and aggressiveness in heroin-dependent males

Notes: += positive,significant; - =negative,significant; ns= nonsignificant; F=females; M=males

Dopamine Receptor 4 (DRD4)
 
Variant Association Phenotype Notes Author
Exon III 48bp repeat Allelic: ns
Genotypic:ns
Suicide attempts Cases: 69 recent adolescent attempters:F:58%; mean age ± SD, 17.7 ± 3.2; Ethnicity: 35 Ashkenazi Jewish Zalsman, 2004
Historical controls: N:167; Ethnicity: 109 Ashkenazi Jewish
Notes: homozygosity for all allele lengths associated with depression severity; Bonferroni-adjusted analyses
Exon III 48bp repeat Allelic: ns
Genotypic :ns
Suicide attempts

Cases: suicide attempters: n:165(F:108); mean age ± SD, 41±17; Ethnicity: Caucasian (77% Swedish,European)

Persson, 1999
Controls: n:99 (F:35); mean age ± SD, 38 ±6; Ethnicity: Caucasian (80% Swedish, European)
Notes: not significant after stratification by diagnosis

Notes: += positive,significant; - =negative,significant; ns=nonsignificant; F=females; M=males

Dopamine Receptor 2 (DRD2)
 
Variant Association Phenotype Notes Author

141CDel/Ins (rs1799732)

TaqIA (rs1800497)

Genotypic:

141CIns, +, χ 2 = 8.429, d.f. = 2, p = 0.015 Logistic regression analysis: –141C Ins/Del genotypes (p = 0.014; OR, 1.95;
95% CI: 1.15–3.32

 

TaqIA,A2, +,χ2 = 6.76, d.f. =
2, p = 0.034 Logistic regression analysis: (p = 0.014; OR,
1.58; 95% CI, 1.06–2.35

Allelic:

141CIns, +, p = 0.011 OR=1.85, 95%CI: 1.16–
2.94

TaqIA,A2 +, p=0.017 1.56 95% CI: 1.09–2.25

Haplotypic: ns

 

Suicide attempts

Ethnicity: Japanese

 

Suda, 2009

Cases: 120 subjects: (F=62,5%) Suicide attempters

 

Controls:123 unrelated healthy volunteers (F=65,9%)
141CDel/Ins Allelic: +, 141CDel, 1.29, 95%CI 1.02-1.64 Suicide attempts or suicidal ideas Ethnicity: Caucasian, German Johann, 2005
Cases: 1126 (F:24%) alcoholic inpatients, including 209 suicidal patients; mean age:43.3±9.7
Controls: 232 individuals without axis I diagnosis or prior psychiatric treatment
Notes: Bonferroni corrected; this allele also associated with family history of alcoholism

Promoter locus

Genotypic: ns

Suicide attempts

Ethnicity: English, Caucasian

Ho, 2000
Cases: Bipolar (M:58, F: 73 female) and  unipolar patients (M:53, F: 86)
Notes: in the unipolar sample, the promoter locus associated with history of psychotic symptoms; uncorrected for multiple testing
Exon 8 A/G Genotypic: +,AA, 1.67, 95%CI 1.1-2.5 Suicide attempts

Ethnicity: Caucasian, German

Finckh, 1997
Cases: 283 alcoholic patients (F:50): mean age: 43±9
Non-alcoholic controls: 146 (F:76); mean age: 54±6
Notes: AA genotype associated with anxiety and depresion scores but not with alcoholism

Notes: += positive,significant; - =negative,significant; ns= nonsignificant; F=females; M=males

Dopamine beta-hydroxylase (dopamine beta-monooxygenase) (DBH)
 
Variant Association Phenotype Notes Author
 

(CA)n

Allelic: ns Suicidal behaviour severity Cases: 336 (F:62%) bipolar patients from 305 nuclear families (mean age: 35.36± 10.37 SD), including 267 patients with suicide ideas or attempts De Luca, 2007

Notes: suicidality assessed quantitatively and coded as follows: 0 = absence of suicide/death thoughts, 1 = thoughts of death, 2 = suicide ideation, 3 = suicide plan, 4 = suicide attempt;

Notes: += positive,significant; -=negative,significant; ns= nonsignificant; F=females; M=males

DOPA decarboxylase-aromatic L-amino acid decarboxylase (DDC)
 
Variant Association Phenotype Sample Information Author
rs1451371 rs1470750 rs998850 Allelic:ns Genotypic:ns Haplotypic: ns Suicide attempts Etnicity: German Giegling, 2009
Cases: 111 suicide attempters, M=43; F= 68; mean age 39.2 ± 13.6
Controls: 289 subjects M=123 F=166; mean age 45.2 ± 14.9

rs1451371, rs1470750, rs998850

Allelic: ns
Genotypic: ns Haplotypic: ns

Suicide & suicide attempts

Ethnicity: German

Giegling, 2007

Cases: 167 suicide attempters (M:58, F:109; mean age, 39.89 ± 13.89), including 60 violent and 101 impulsive attempters

Cases: 92 Caucasian suicide completers (M:53, F:39; mean age: 51.8 ± 18.5)

Controls: unrelated German volunteers without personal/ family history of neuropsychiatric disorders (F:174, M:138; mean age: 45.01±14.92)

Notes: excluded stratification using genomic control; no association with personality traits; stratified for violence, impulsiveness, completion versus attempt; marginal associations with suicide, violence, anger, and aggression

Notes: += positive,significant; - =negative,significant; ns= nonsignificant; F=females; M=males

Catechol-O-methyltransferase (COMT)
 
Variant Association Phenotype Notes Author

Val158Met

 

Allelic: ns Suicidal behaviour severity Cases: 336 (F:62%) bipolar patients from 305 nuclear families (mean age: 35.36± 10.37 SD), including 267 patients with histories of suicide ideas or attempts De Luca, 2007

Notes: suicidality assessed a quantitatively and coded as follows: 0 = absence of suicide/death thoughts, 1 = thoughts of death, 2 = suicide ideation, 3 = suicide plan, 4 = suicide attempt

287AG Allelic: ns
Suicide attempts Sample: schizophrenic patients (n:270): suicide attempters: 92 (F:24), mean age:42.6±9.7; nonattempters: mean age:40.6±11.2 De Luca, 2006
Val/Met Allelic: ns Notes: Investigated one MAO and three COMT variants; analyses also stratified by sex and violence of attempt method
3'UTR C Ins/Del Allelic: ns
  Haplotypic: ns
Epistatic interaction with MAO's uVNTR: ns
Val108/158Met Allelic: ns Suicide attempts Sample: 336 bipolar patients (F:62%) including 86 suicide attempters; mean age:35.36±10.37 De Luca, 2005
Notes: Analyses based on TDT; suicidality also assessed quantitatively
Epistatic interaction with MAOA: ns
Val108/158Met Allelic:+, L, OR 1.57, 95% CI 1.04-2.38, relative to controls

Violent suicide attempts

Ethnicity: German Rujescu, 2003
Allelic:+, L, OR 1.7, 95% CI 1.07-2.79, relative to nonviolent attempters Suicide attempters: F:96, M:53; mean age:40±13; violent attempters:55]
Genotypic: +, LL, OR=2.12, 95% CI 1.18-3.83, relative to controls Community controls: F:179,M:149; mean age: 46±15]
Genotypic: +, LL, OR=2.35, 95% CI 1.15-4.82, relative to nonviolent attempters Notes: LL carriers expressed anger outwardly and HH carriers more inwardly, controlling for age and sex
Val158Met Allelic: ns
Genotypic: ns
Suicide attempts Ethnicity: Chinese, Taiwan; Liou, 2001
Cases: schizophrenic patients [F:104,M:94; mean age: 37.8±12.1], including 62 suicide attempters
Healthy volunteer controls: F:91,M:97; mean age: 38.6±16.6
Notes: not associated with schizophrenia with or without violence
Val108/158Met Allelic:+,Met, p=.05, men
Genotypic: +, Met-, p=.017, men
Violent suicide attempts Ethnicity: Finnish nonSaami sample: n:94 (F:10, mean age: 41.8, 57 suicide attempters) and USA sample (White, 4 Hispanic): n: 54 (F:21, mean age: 42.9, 27 suicide attempters) Nolan, 2000
Cases: schizophrenic/ schizoaffective attempters and nonattempters
Allelic:+, Met, p=.008, men
Genotypic: +, Met-, p=.028, men
Suicide attempts Notes: association found in the combined samples and in the Finnish sample on its own
L/H Allelic: ns
Genotypic: ns
Suicide attempts Ethnicity: Japanese Ohara, 1998
Cases: 12 mood-disordered patients [M:60, F:55; suicide attempters; mean age:48.5±16.3]
Healthy controls: N:135
Notes: positive association of LL genotype with depressive disorders [p=.012, OR=2.19; 95%CI 1.19-4.03]
Val108/158Met

Allelic: ns
Genotypic: -,Val/Val, OR .52 95% .31-.89, males

Genotypic: +,Val/Met, OR 1.98 95% 1.16-3.37, males

Suicide Cases: suicide completers: M:112; mean age:48.68±16.9; F:51; mean age: 47.12±19.8 Ono, 2004
Controls: M:114; mean age:45.33±15.5; F:55; mean age: 48.9±18.7
Notes: trend toward deviation from HW equilibrium in male completers
Val108/158Met
Genotypic: ns
Suicide risk Cases: patients at high risk for suicide: F:32,M:19; mean age:38±15; Caucasian (n:41), African-American (n:6), and Hispanic, Indian, and Asian (n:4) Russ, 2000
Race-matched controls: F:28,M:23; mean age:41±13
Notes:Bonferroni corrected

Notes: += positive,significant; - =negative,significant; ns= nonsignificant; F=females; M=males

Monoamino oxidase A (MAOA)
 
Variant Association Phenotype Sample Information Author

uVNTR

Allelic: ns
Epistasis with COMT: ns

Suicide attempts

Cases: 270 schizophrenic patients: 92 (F:24) suicide attempters (mean age: 42.6±9.7) and 178 nonattempters (mean age: 40.6±11.2)

De Luca, 2006

Notes: Investigated one MAO and three COMT; also stratified by sex and violence of suicide attempt

uVNTR

 

Allelic: ns
Genotypic: +,2-3 alleles, OR: 2.17 95% CI 1.08-4.35, males

Violent

suicide attempts

Ethnicity: West European, Caucasian

 

Courtet, 2005

 

Hospitalized suicide attempters: F:512; M:226; mean age: 38.08 ± 14.12

CAn Allelic: ns
Suicide attempts Non-psychiatric controls without first-degree family history of suicide attempts: F:68, M:154; mean age: 44.25±13.26
Notes: CAn is in LD with uVNTR

 

uVNTR

T941G

Allelic: ns

Haplotypic: ns

Epistasis with COMT: ns

Suicide attempts

Sample: 336 bipolar patients (F:62%) including 86 suicide attempters; mean age:35.36±10.37

De Luca, 2005
Notes: analyses based on TDT; No epistasis with COMT  Val108/158 Met

uVNTR

Allelic: ns

Suicide attempts

Ethnicity: white Caucasian, Italian

Gerra, 2004
Heroin –dependent males: n:104; mean age: 33.7±12.3
Age- and sex-matched healthy volunteers: n:95; mean age: 35.7±13.9
Notes: this variant confers increased susceptibility to antisocial violent behavior and aggressiveness in heroin-dependent males

uVNTR

Allelic: ns
Genotypic: ns

Suicide attempts

Cases: mood-disordered patients: F:377, M:286; mean age: 37.6 ±12.9; Caucasian: 68.8%; African-Americans 16.6%; Asian, Hispanic and ‘’other" 14.6%

Huang, 2004
Nonpsychiatric controls with comparable ethnic composition: F:47, M:56; mean age: 38.8 ±15.3
Notes: lower expression allele associated with history of child abuse before 15 years of age and higher impulsivity in males

CAn

ns

Suicide attempts

Ethnicity: English, Caucasian

Ho, 2000
VNTR

Genotypic: +, VNTR, ,p=0.029, bipolar patients

Cases: bipolar (M:58, F: 73) and  unipolar patients (M:53, F: 86)
Fnu4HI Genotypic:+, 11, p=0.0162, female bipolar patients Notes: VNTR’s association with suicide  attempts stronger in females; uncorrected for multiple testing

VNTR

Allelic: ns
Genotypic: ns
Suicide attempts

Ethnicity: Japanese

Kunugi, 1999
Patients with bipolar disorder (M:59, F:102; mean age: 47.6±13.7) or unipolar (F:61, M:37; mean age: 54.5±16.4), including 55 suicide attempters
Controls: M:132; F:126 mean age: 31.8.6±12.3
Notes: no association with mood disorders
EcoRV

Allelic: +,high-activity allele, OR:3.1, 95% CI 1.3-7.5, males

Suicide

Ethnicity: Caucasian, Hungary

Du, 2002
Depressed suicide completers: F:11; M:33 mean age: 47.9±14.4
Controls who died of non-suicide-related causes: F:28; M:64 mean age: 57.5±13.6
Notes: Bonferroni-corrected
uVNTR Allelic: ns
Genotypic: ns
Suicide

Ethnicity: Japanese

Ono, 2002
Cases: suicides [M: 107; mean age: 48.4 ±16.6; F: 48; mean age: 47.6± 19.9]
Healthy volunteers [M: 109; mean age: 45.1± 15.3; F: 53; mean age: 48.4±18.8]

Notes: += positive,significant; - =negative,significant; ns= nonsignificant; F=females; M=males