Impact of DRD2/ANKK1 and COMT Polymorphisms on Attention and Cognitive Functions in Schizophrenia

Association of SLC6A3 variants with treatment-resistant schizophrenia: a genetic association study of dopamine-related genes in schizophrenia

Background

Most genetic analyses that have attempted to identify a locus or loci that can distinguish patients with treatment-resistant schizophrenia (TRS) from those who respond to treatment (non-TRS) have failed. However, evidence from multiple studies suggests that patients with schizophrenia who respond well to antipsychotic medication have a higher dopamine (DA) state in brain synaptic clefts whereas patients with TRS do not show enhanced DA synthesis/release pathways.

Patients and methods

To examine the contribution (if any) of genetics to TRS, we conducted a genetic association analysis of DA-related genes in schizophrenia patients (TRS, n = 435; non-TRS, n = 539) and healthy controls (HC: n = 489).

Results

The distributions of the genotypes of rs3756450 and the 40-bp variable number tandem repeat on SLC6A3 differed between the TRS and non-TRS groups. Regarding rs3756450, the TRS group showed a significantly higher ratio of the A allele, whereas the non-TRS group predominantly had the G allele. The analysis of the combination of COMT and SLC6A3 yielded a significantly higher ratio of the putative low-DA type (i.e., high COMT activity + high SLC6A3 activity) in the TRS group compared to the two other groups. Patients with the low-DA type accounted for the minority of the non-TRS group and exhibited milder psychopathology.

Conclusion

The overall results suggest that (i) SLC6A3 could be involved in responsiveness to antipsychotic medication and (ii) genetic variants modulating brain DA levels may be related to the classification of TRS and non-TRS.

Effects of mind-body therapies on schizophrenia: A systematic review and network meta-analysis

OBJECTIVE

The objective of this meta-analysis is to evaluate and compare the effectiveness of different mind-body therapies in reducing the symptoms of schizophrenia.

METHODS

A systematic search was performed using databases such as PubMed, Embase, Cochrane Library, Web of Science, and Scopus. Randomized controlled trials that assessed the effects of mind-body therapies on patients with schizophrenia were included. The search covered the period between the inception of each database and November 17th, 2022. The methodological quality of the trials was assessed using the Cochrane risk of bias tool. A network meta-analysis was conducted to compare the effects of various mind-body therapies, including Yoga, Mindfulness, Tai Chi, Baduanjin, and Yijinjing.

RESULTS

The analysis included 22 randomized controlled trials involving a total of 2064 subjects. The network meta-analysis revealed that Yoga and Mindfulness interventions were more effective than other mind-body therapies in reducing the symptoms of schizophrenia. Specifically, Yoga improved PANSS-positive symptom scores (SUCRA: 74.8 %) and PANSS-negative symptom scores (SUCRA: 80.4 %), whereas Mindfulness improved PANSS-positive symptom scores (SUCRA: 85.6 %).

CONCLUSION

The findings of this study indicate that Yoga may be a promising intervention for the treatment of schizophrenia. However, the small sample size and the low quality of the included studies have limited the generalizability of our findings Therefore, this study must be understood with caution, and further investigation is warranted when more relevant studies emerge.

Genetic Variants Associated with Suicide Risk in the Mexican Population: A Systematic Literature Review

Suicide is defined as the action of harming oneself with the intention of dying. It is estimated that worldwide, one person dies by suicide every 40 s, making it a major health problem. Studies in families have suggested that suicide has a genetic component, so the search for genetic variants associated with suicidal behavior could be useful as potential biomarkers to identify people at risk of suicide. In Mexico, some studies of gene variants related to neurotransmission and other important pathways have been carried out and potential association of variants located in the following genes has been suggested: SLC6A4, SAT-1, TPH-2, ANKK1, GSHR, SCARA50, RGS10, STK33, COMT, and FKBP5. This systematic review shows the genetic studies conducted on the Mexican population. This article contributes by compiling the existing information on genetic variants and genes associated with suicidal behavior, in the future could be used as potential biomarkers to identify people at risk of suicide.

Lifetime cannabis use and childhood trauma associated with CNR1 genetic variants increase the risk of psychosis: findings from the STREAM study

OBJECTIVES

Gene-environment interactions increase the risk of psychosis. The objective of this study was to investigate gene-gene and gene-environment interactions in psychosis, including single nucleotide variants (SNVs) of dopamine-2 receptor (D2R), N-methyl-d-aspartate receptor (NMDAR), and cannabinoid receptor type 1 (CB1R), lifetime cannabis use, and childhood trauma.

METHODS

Twenty-three SNVs of genes encoding D2R (DRD2: rs1799978, rs7131056, rs6275), NMDAR (GRIN1: rs4880213, rs11146020; GRIN2A: rs1420040, rs11866328; GRIN2B: rs890, rs2098469, rs7298664), and CB1R (CNR1: rs806380, rs806379, rs1049353, rs6454674, rs1535255, rs2023239, rs12720071, rs6928499, rs806374, rs7766029, rs806378, rs10485170, rs9450898) were genotyped in 143 first-episode psychosis patients (FEPp) and 286 community-based controls by Illumina HumanCoreExome-24 BeadChip. Gene-gene and gene-environment associations were assessed using nonparametric Multifactor Dimensionality Reduction software.

RESULTS

Single-locus analyses among the 23 SNVs for psychosis and gene-gene interactions were not significant (p > 0.05 for all comparisons); however, both environmental risk factors showed an association with psychosis (p < 0.001). Moreover, gene-environment interactions were significant for an SNV in CNR1 and cannabis use. The best-performing model was the combination of CNR1 rs12720071 and lifetime cannabis use (p < 0.001), suggesting an increased risk of psychosis.

CONCLUSION

Our study supports the hypothesis of gene-environment interactions for psychosis involving T-allele carriers of CNR1 SNVs, childhood trauma, and cannabis use.

Gender divergent effect of COMT gene rs4680 polymorphism on the association between executive dysfunction and psychotic-like experiences

AIM

Premorbid cognitive impairments are observed prior to the onset of schizophrenia. Catechol-O-methyltransferase (COMT) rs4680 is associated with psychosis and plays a crucial role in the development of the executive function. In addition, genetic COMT variations and gender affect its enzymatic activity. Therefore, the aim of this study was to evaluate the impact of COMT rs4680 on the relationship between executive dysfunction and psychotic-like experiences (PLEs) in college students, with the additional investigation of the gender difference.

METHODS

A total of 463 students provided biological samples for DNA analysis and the COMT gene rs4680 polymorphism was discriminated by the improved multiplex ligase detection reaction method. They also completed the Prodromal Questionnaire and the Dysexecutive Questionnaire.

RESULTS

Executive dysfunction significantly predicted positive PLEs in the total, male and female population (β = 0.515, 0.508 and 0.512, p < 0.001). The results of moderated analysis revealed that COMT rs4680 recessive genetic model ('AA genotype' versus 'G carrier') moderated the relationship between executive dysfunction and psychotic-like experience in the total and females (p = 0.002 and p <0.001, respectively), but not in males.

CONCLUSION

These findings revealed a female-specific effect of COMT rs4680 on the relationship between executive dysfunction and PLEs in young adults.

The Interplay Between Prenatal Adversity, Offspring Dopaminergic Genes, and Early Parenting on Toddler Attentional Function

Background: Few studies have explored the complex gene-by-prenatal environment-by-early postnatal environment interactions that underlie the development of attentional competence. Here, we examined if variation in dopamine-related genes interacts with prenatal adversity to influence toddler attentional competence and whether this influence is buffered by early positive maternal behavior. Methods: From the Maternal Adversity, Vulnerability and Neurodevelopment cohort, 134 participants (197 when imputing missing data) had information on prenatal adversity (prenatal stressful life events, prenatal maternal depressive symptoms, and birth weight), five dopamine-related genes (DAT1, DRD4, DRD2, COMT, BDNF), observed maternal parenting behavior at 6 months and parent-rated toddler attentional competence at 18 and 24 months. The Latent Environmental and Genetic Interaction (LEGIT) approach was used to examine genes-by-prenatal environment-by-postnatal environment interactions while controlling for sociodemographic factors and postnatal depression. Results: Our hypothesis of a three-way interaction between prenatal adversity, dopamine-related genes, and early maternal parenting behavior was not confirmed. However, consistent two-way interactions emerged between prenatal adversity and dopamine-related genes; prenatal adversity and maternal parenting behavior, and dopamine-related genes and maternal parenting behavior in relation to toddler attentional competence. Significant interaction effects were driven by the DAT1, COMT, and BDNF genotypes; prenatal stressful life events; maternal sensitivity, tactile stimulation, vocalization, and infant-related activities. Conclusions: Multiple dopamine-related genes affected toddler attentional competence and they did so in interaction with prenatal adversity and the early rearing environment, separately. Effects were already visible in young children. Several aspects of early maternal parenting have been identified as potential targets for intervention.

Long acting aripiprazole influences cognitive functions in recent onset schizophrenia

RATIONALE

Beneficial effects of aripiprazole on cognition in schizophrenia have been previously reported, but not in recent onset schizophrenia. Cognitive impairments have also been associated with catechol-O-methyltransferase (COMT), methylenetetrahydrofolate reductase (MTHFR), and serotonin transporter (SERT) gene polymorphisms which were earlier implicated in the pathophysiology of schizophrenia.

OBJECTIVES

This study examined the short-term influence of aripiprazole long-acting injectable (LAI) as well as of COMT, MTHFR, and SERT gene polymorphisms and their interactions on clinical features and cognitive functions in inpatients with recent onset schizophrenia.

METHODS

This study included 98 inpatients suffering from recent onset schizophrenia diagnosed according to DSM-5 criteria. Three months after initiating aripiprazole LAI, the severity of symptoms was assessed by the Positive and Negative Syndrome Scale (PANSS), while cognitive functions were measured by 5-KOG test for cognition. Genotypes of SERT, MTHFR, and COMT gene were determined by different polymerase chain reaction (PCR) methods.

RESULTS

Three-month aripiprazole LAI treatment was associated with a statistically significant change of PANSS total (p<0.001) and subscale scores as well as cognitive parameters of delayed recall (p<0.03), attention (p<0.01), and executive functions in the form of less perseverations (p<0.03), without influencing other examined cognitive functions. However, it significantly influenced composite cognitive score (p<0.02). In regard to the investigated genetic polymorphisms, we established a positive association between the COMT polymorphism (M/M allele carriers) and attention (p<0.01). Additionally, we also established a positive association between the COMT - MTHFR interaction and attention (p<0.02), as well as perseveration item belonging to executive functions (p<0.01). Two other investigated polymorphisms (MTHFR and SERT) were not significantly associated with cognitive indices. Investigated genetic polymorphisms and their interactions were not associated with PANSS scores.

CONCLUSIONS

Our findings suggest that aripiprazole LAI improves individual cognitive functions in recent onset schizophrenia. Investigated COMT polymorphism (Met/Met genotype), as well as the COMT-MTHFR interaction, were positively associated with attention and executive functioning (perseveration), potentially implying COMT's biomarker potential in terms of cognition in schizophrenia.

The Pan social brain: An evolutionary history of neurochemical receptor genes and their potential impact on sociocognitive differences

Humans have unique cognitive capacities that, compared with apes, are not only simply expressed as a higher level of general intelligence, but also as a quantitative difference in sociocognitive skills. Humans' closest living relatives, bonobos (Pan paniscus), and chimpanzees (Pan troglodytes), show key between-species differences in social cognition despite their close phylogenetic relatedness, with bonobos arguably showing greater similarities to humans. To better understand the evolution of these traits, we investigate the neurochemical mechanisms underlying sociocognitive skills by focusing on variation in genes encoding proteins with well-documented roles in mammalian social cognition: the receptors for vasopressin (AVPR1A), oxytocin (OXTR), serotonin (HTR1A), and dopamine (DRD2). Although these genes have been well studied in humans, little is known about variation in these genes that may underlie differences in social behavior and cognition in apes. We comparatively analyzed sequence data for 33 bonobos and 57 chimpanzees, together with orthologous sequence data for other apes. In all four genes, we describe genetic variants that alter the amino acid sequence of the respective receptors, raising the possibility that ligand binding or signal transduction may be impacted. Overall, bonobos show 57% more fixed substitutions than chimpanzees compared with the ancestral Pan lineage. Chimpanzees, show 31% more polymorphic coding variation, in line with their larger historical effective population size estimates and current wider distribution. An extensive literature review comparing allelic changes in Pan with known human behavioral variants revealed evidence of homologous evolution in bonobos and humans (OXTR rs4686301(T) and rs237897(A)), while humans and chimpanzees shared OXTR rs2228485(A), DRD2 rs6277(A), and DRD2 rs11214613(A) to the exclusion of bonobos. Our results offer the first in-depth comparison of neurochemical receptor gene variation in Pan and put forward new variants for future behavior-genotype association studies in apes, which can increase our understanding of the evolution of social cognition in modern humans.

Genetic diversity of the North African population revealed by the typing of SNPs in the DRD2/ANKK1 genomic region

The dopamine - related genes, like dopamine D2 receptor (DRD2) gene and ankyrin repeat and kinase domain containing 1 (ANKK1) gene are implicated in neurological functions. Some polymorphisms of the DRD2/ANKK1 locus (TaqIA, TaqIB, TaqID) have been used to study genetic diversity and the evolution of human populations. The present investigation aims to assess the genetic diversity in seven North African populations in order to explore their genetic structure and to compare them to others worldwide populations studied for the same locus. Nine single nucleotide polymorphisms (SNPs) from the DRD2/ANKK1 locus (rs1800497 TaqIA, rs2242592, rs1124492, rs6277, rs6275, rs1079727, rs2002453, rs2234690 and rs1079597 TaqIB) were typed in 366 individuals from seven North African populations: six from Tunisia (Sousse, Smar, Kesra, Kairouan, Mehdia and Kerkennah) and one from Libya. The allelic frequencies of rs2002453 and rs2234690 were higher in the Smar population than in the other North African populations. More, the Smar population showed the lowest average heterozygosity (0.313). The principal component analysis (PCA) showed that the Smar population was clearly separated from others. Furthermore, linkage disequilibrium analysis shown a high linkage disequilibrium in the North African population and essentially in Smar population. Comparison with other world populations has shown that the heterozygosity of North African population was very close to that of the African and European populations. The PCA and the haplotypic analysis suggested the presence of an important Eurasian genetic component for the North African population. These results suggested that the Smar population was isolated from the others North Africans ones by its peculiar genetic structure because of isolation, endogamy and genetic drift. On the other hand, the North African population is characterized by a multi ancestral gene pool from Eurasia and sub-Saharan Africa due to human migration since prehistoric times.

Central Nervous System Plasticity Influences Language and Cognitive Recovery in Adult Glioma

Gliomas exist within the framework of complex neuronal circuitry in which network dynamics influence both tumor biology and cognition. The generalized impairment of cognition or loss of language function is a common occurrence for glioma patients. The interface between intrinsic brain tumors such as gliomas and functional cognitive networks are poorly understood. The ability to communicate effectively is critically important for receiving oncological therapies and maintaining a high quality of life. Although the propensity of gliomas to infiltrate cortical and subcortical structures and disrupt key anatomic language pathways is well documented, there is new evidence offering insight into the network and cellular mechanisms underpinning glioma-related aphasia and aphasia recovery. In this review, we will outline the current understanding of the mechanisms of cognitive dysfunction and recovery, using aphasia as an illustrative model.

Association of DRD2 gene polymorphisms with schizophrenia in the young Bangladeshi population: A pilot study

Purpose

DRD2 gene is considered one of the most important candidate genes for the schizophrenia (SCZ) development due to its role in dopamine signaling and no genetic association study has been conducted yet on the Bangladeshi SCZ patients. The objective of the present study was to investigate the association of DRD2 genetic polymorphisms (rs4648317, rs4936270, and rs7131056) with SCZ in the Bangladeshi population.

Patients and methods

This case-control study consisted of 101 SCZ patients and 101 controls. Genotyping was performed by the polymerase chain reaction and restriction fragment length polymorphism (PCR–RFLP) method.

Results

The average ages were 22.15 and 22.09 years in patients and controls, respectively (p > 0.05). CT genotype of rs4936270 showed a significantly higher risk for the development of SCZ compared to CC genotype (OR = 2.0, p = 0.023), whereas no association was found for TT genotype. For the dominant model and T allele, rs4936270 showed a higher risk for the development of SCZ (OR = 2.01, p = 0.020; OR = 1.76, p = 0.021, respectively), while the recessive model had no association with SCZ. A statistically significant (OR = 2.70, p = 0.036) higher risk was found for the AA genotype, but no association was found for GA genotype of rs4648317 SNP compared to GG genotype. In case of dominant and recessive models, rs4648317 showed no association with SCZ. ‘A’ allele of rs4648317 SNP was found to be significantly associated with the elevated risk of SCZ (OR = 1.50, p = 0.044). No association with SCZ of rs7131056 SNP was found for AC, CC genotypes, dominant, recessive, and allele models. Furthermore, from the haplotyping analysis, we found that CAA and TAA haplotypes of rs4936270, rs7131056 and rs4648317 SNPs are associated with SCZ (χ2 = 8.26, p = 0.004; χ2 = 5.31, p = 0.021, respectively). After Bonferroni correction, the association of SCZ did not withstand with any genotype, allele and haplotype (p < 0.017) except CAA haplotype.

Conclusion

Our results suggest that DRD2 gene polymorphisms may be associated with the susceptibility of SCZ in the young Bangladeshi population.

[A new look at the genetics of neurocognitive deficits in schizophrenia]

The article presents current literature data on genetic studies of neurocognitive deficit in schizophrenia, including the genes of neurotransmitter systems (dopaminergic, glutamatergic, and serotonergic); genes analyzed in genome-wide association studies (GWAS), as well as other genetic factors related to the pathophysiological mechanisms underlying schizophrenia and neurocognitive disorders.

Association of ANKK1 polymorphism with antipsychotic-induced hyperprolactinemia

OBJECTIVE

Schizophrenia is a severe highly heritable mental disorder. Genetic polymorphisms of dopaminergic pathways are related to pathogenesis of drug response. Hyperprolactinemia (HPRL), a common adverse effect of antipsychotics, is attributed to blockade of dopamine D2 receptors. Ankyrin Repeat and Kinase Domain containing 1 (ANKK1) gene is closely related to Dopamine Receptor D2 type (DRD2) gene functioning. We examined whether the functional polymorphism rs2734849 in the ANKK1 gene is associated with antipsychotic-induced HPRL.

METHODS

We recruited 446 patients with schizophrenia from among the Russian population of the Siberian region. The polymorphism rs2734849 in the ANKK1 gene was genotyped with The MassARRAY® Analyzer 4 by Agena Bioscience™, using the kit SEQUENOM Consumables iPLEXGold 384. Genotype and allele frequencies were compared between groups of schizophrenia patients with and without HPRL using the χ² test.

RESULTS

A comparison between schizophrenia patients with and without HPRL revealed significantly higher frequency of the C allele of the polymorphic variant rs2734849 in the ANKK1 gene in patients with HPRL as compared to the patients without it (χ² = 3.70; p = .05; odds ratio [OR] = 1.30 [0.99-1.69]).

CONCLUSION

The functional polymorphism rs2734849 in the ANKK1 gene was associated with HPRL in patients with schizophrenia.

Ankyrin Repeat and Kinase Domain Containing 1 Gene, and Addiction Vulnerability

The TaqIA single nucleotide variant (SNV) has been tested for association with addictions in a huge number of studies. TaqIA is located in the ankyrin repeat and kinase domain containing 1 gene (ANKK1) that codes for a receptor interacting protein kinase. ANKK1 maps on the NTAD cluster along with the dopamine receptor D2 (DRD2), the tetratricopeptide repeat domain 12 (TTC12) and the neural cell adhesion molecule 1 (NCAM1) genes. The four genes have been associated with addictions, although TTC12 and ANKK1 showed the strongest associations. In silico and in vitro studies revealed that ANKK1 is functionally related to the dopaminergic system, in particular with DRD2. In antisocial alcoholism, epistasis between ANKK1 TaqIA and DRD2 C957T SNVs has been described. This clinical finding has been supported by the study of ANKK1 expression in peripheral blood mononuclear cells of alcoholic patients and controls. Regarding the ANKK1 protein, there is direct evidence of its location in adult and developing central nervous system. Together, these findings of the ANKK1 gene and its protein suggest that the TaqIA SNV is a marker of brain differences, both in structure and in dopaminergic function, that increase individual risk to addiction development.

Polygenic Risk Scores Shed Light on the Relationship between Schizophrenia and Cognitive Functioning: Review and Meta-Analysis

Schizophrenia is a multifactorial disease associated with widespread cognitive impairment. Although cognitive deficits are one of the factors most strongly associated with functional impairment in schizophrenia (SZ), current treatment strategies hardly tackle these impairments. To develop more efficient treatment strategies in patients, a better understanding of their pathogenesis is needed. Recent progress in genetics, driven by large genome-wide association studies (GWAS) and the use of polygenic risk scores (PRS), has provided new insights about the genetic architecture of complex human traits, including cognition and SZ. Here, we review the recent findings examining the genetic links between SZ and cognitive functions in population-based samples as well as in participants with SZ. The performed meta-analysis showed a negative correlation between the polygenetic risk score of schizophrenia and global cognition (p < 0.001) when the samples rely on general and healthy participants, while no significant correlation was detected when the three studies devoted to schizophrenia patients were meta-analysed (p > 0.05). Our review and meta-analysis therefore argues against universal pleiotropy for schizophrenia alleles and cognition, since cognition in SZ patients would be underpinned by the same genetic factors than in the general population, and substantially independent of common variant liability to the disorder.

Cannabis and Psychosis Through the Lens of DSM-5

Evidence for an association between cannabis and psychosis has been documented in literature in many forms including experimental studies, epidemiological data, and case series. The association has implications for psychotic outcomes ranging from mild to severe and occurring over minutes to years. Due to the huge variety of exposures and outcome measures reported, creating a coherent account of all the available information is difficult. A useful way to conceptualize these wide-ranging results is to consider the association between cannabis and psychosis as it occurs within the context of widely used DSM-5 diagnoses. In the present review we examine cannabis/psychosis associations as they pertain to Cannabis Intoxication, Cannabis-Induced Psychotic Disorder, and Schizophrenia. This allows for an understanding of the cannabis and psychosis association along something approaching a continuum. Cannabis intoxication becomes Cannabis-Induced Psychotic Disorder once certain severity and duration criteria are met and Cannabis-Induced Psychotic Disorder is heavily associated with future schizophrenia diagnoses.

The effect of ANKK1 Taq1A and DRD2 C957T polymorphisms on executive function: A systematic review and meta-analysis

Research in healthy adults suggests that C957T polymorphism of the dopamine D2 receptor encoding DRD2 and the Taq1A polymorphism of the neighbouring gene ankyrin repeat and kinase domain containing 1 (ANKK1) alter dopaminergic signalling and may influence prefrontally-mediated executive functions. A systematic review and meta-analysis was carried out on the evidence for the association of DRD2 C957T and ANKK1 Taq1A polymorphisms in performance on tasks relating to the three core domains of executive function: working memory, response inhibition and cognitive flexibility in healthy adults. CINAHL, MEDLINE, PsycARTICLES and PsychINFO databases were searched for predefined key search terms associated with the two polymorphisms and executive function. Studies were included if they investigated a healthy adult population with the mean age of 18-65 years, no psychiatric or neurological disorder and only the healthy adult arm were included in studies with any case-control design. Data from 17 independent studies were included in meta-analysis, separated by the Taq1A and C957T polymorphisms and by executive function tests: working memory (Taq1A, 6 samples, n = 1270; C957 T, 6 samples, n = 977), cognitive flexibility (C957 T, 3 samples, n = 620), and response inhibition (C957 T, 3 samples, n = 598). The meta-analyses did not establish significant associations between these gene polymorphisms of interest and any of the executive function domains. Theoretical implications and methodological considerations of these findings are discussed.

Association between Polymorphisms of the DRD2 and ANKK1 Genes and Suicide Attempt: A Preliminary Case-Control Study in a Mexican Population

BACKGROUND

The aim of this study was to analyze the possible association of polymorphic variants of the DRD2 and ANKK1 genes with suicide attempt in a Mexican population.

METHODS

We conducted a case-control study in 289 subjects (166 suicide attempters and 123 healthy controls). We genotyped 2 polymorphisms of DRD2 (rs6275 and rs1799978) and 1 polymorphism of ANKK1 (rs1800497); then we analyzed the association between suicide attempt and these polymorphisms through genotypes, alleles, and inheritance models.

RESULTS

Individuals who carried the TT genotype of the rs1800497 showed a 3-fold risk of attempting suicide (OR = 3.01; 95% CI 1.56-5.81, p = 0.001) when evaluated through the recessive model. In an analysis stratified by gender, this risk factor remained present among females (OR = 2.81; 95% CI 1.37-5.75) as well as males (OR = 3.3; 95% CI 1.01-10.77).

CONCLUSION

Our results suggest that the rs1800497 variant of the ANKK1 gene could increase the risk of suicide attempt in a Mexican population. However, further studies using larger samples are necessary to obtain more conclusive results.