Association of BDNF with restricting anorexia nervosa and minimum body mass index: a family-based association study of eight European populations

Eating disorders (ED), such as anorexia nervosa (AN) and bulimia nervosa (BN), are complex psychiatric disorders where different genetic and environmental factors are involved. Several lines of evidence support that brain-derived neurotrophic factor (BDNF) plays an essential role in eating behaviour and that alterations on this neurotrophic system participates in the susceptibility to both AN and BN. Accordingly, intraventricular administration of BDNF in rats determines food starvation and body weight loss, while BDNF or its specific receptor NTRK2 knockout mice develop obesity and hyperphagia. Case-control studies also suggest a BDNF contribution in the aetiology of ED: we have previously reported a strong association between the Met66 variant within the BDNF gene, restricting AN (ANR) and minimum body mass index (minBMI) in a Spanish sample, and a positive association between the Val66Met and -270C/T BDNF SNPs and ED in six different European populations. To replicate these results, avoiding population stratification effects, we recruited 453 ED trios from eight European centres and performed a family-based association study. Both haplotype relative risk (HRR) and haplotype-based haplotype relative risk (HHRR) methods showed a positive association between the Met66 allele and ANR. Consistently, we also observed an effect of the Met66 variant on low minBMI and a preferential transmission of the -270C/Met66 haplotype to the affected ANR offspring. These results support the involvement of BDNF in eating behaviour and further suggest its participation in the genetic susceptibility to ED, mainly ANR and low minBMI.     

No association of the Arg51Gln and Leu72Met polymorphisms of the ghrelin gene with anorexia nervosa or bulimia nervosa

Genetic factors likely contribute to the biological vulnerability to anorexia nervosa (AN) and bulimia nervosa (BN). We investigated whether the Arg51Gln and/or the Leu72Met gene polymorphisms of the human ghrelin, a peptide involved in the regulation of eating behavior, were associated to AN and/or BN. Two-hundred-ninety-two Caucasian women (114 with BN, 59 with AN and 119 healthy controls) participated into the study. No significant differences were found in the frequencies of the Arg51Gln and the Leu72Met ghrelin gene variants among patients with AN or BN and healthy controls. Moreover, no significant differences emerged in eating-related phenotypic variables between patients carrying the Leu72Met genotype as compared to those with the Leu72Leu genotype. These results suggest that the Arg51Gln and the Leu72Met polymorphisms of the human ghrelin gene do not contribute to the genetic susceptibility to AN and BN.     

Circulating brain-derived neurotrophic factor is decreased in women with anorexia and bulimia nervosa but not in women with binge-eating disorder: relationships to co-morbid depression, psychopathology and hormonal variables

BACKGROUND: Several lines of evidence indicate a role of the brain-derived neurotrophic factor (BDNF) in the modulation of eating behaviour. Therefore, alterations in the physiology of this neurotrophin may be involved in the pathogenesis of eating disorders. In the present study, we investigated serum levels of BDNF in patients with anorexia nervosa (AN), bulimia nervosa (BN) and binge-eating disorder (BED). METHOD: Ninety-nine drug-free women (27 with AN, 24 with BN, 24 with BED and 24 healthy controls) underwent both a blood sample collection in the morning and diagnostic and psychopathological assessments by means of structured clinical interviews and ad-hoc rating scales. Serum levels of BDNF, 17 beta-oestradiol, FT3 and FT4 were measured. RESULTS: Compared to healthy controls, serum levels of BDNF were significantly reduced in underweight AN women and in normal weight BN women, but not in overweight BED women. Changes in circulating BDNF levels were not affected by the presence of co-morbid depressive disorders. No significant correlation emerged between neurotrophin concentrations and psychopathological, nutritional, demographic and hormonal variables. CONCLUSIONS: These findings evidentiate alterations in serum BDNF levels in malnourished patients with AN or BN, but not in well-nourished individuals with BED. Since BDNF seems to exert a satiety effect, its reduction may represent an adaptive change to counteract the decreased calorie ingestion of AN and BN individuals.     

No association of brain-derived neurotrophic factor Val66Met polymorphism with anorexia nervosa in Japanese

The Met66 allele of the Val66Met polymorphism in the brain-derived neurotrophic factor (BDNF) gene has been reported to be associated with anorexia nervosa (AN), and also lower minimum body mass index (BMI) and higher harm avoidance in AN. We genotyped the Val66Met polymorphism (rs6265) in 689 AN cases and 573 control subjects. There were no significant differences in the genotype or allele frequencies of the Val66Met between AN and control subjects (allele wise, odds ratio?=?0.920, 95% CI 0.785-1.079, P?=?0.305). No difference was found in minimum BMIs related to Val66Met in AN (one-way ANOVA, P?>?0.05). Harm avoidance scores on the Temperament and Character Inventory were lower in the Met66 allele carriers (P?=?0.0074) contrary to the previous report. Thus we were unable to replicate the previous findings that the Met66 allele of the BDNF is associated with AN and that the minimum BMI is lower or the harm avoidance score is higher in AN patients with the Met66 allele.     

Co-occurrence of eating disorders and alcohol use disorders in women: a meta analysis

Summary This meta analysis involved 41 studies published between January of 1985 and May of 2006, which examined the co-occurrence of eating disorders (ED) and alcohol use disorders (AUD) in women. Studies were reviewed and a quantitative synthesis of their results was carried out via the calculation of standardised effect sizes. Direction and strength of the relationships between AUD and specific disordered eating patterns were examined. Heterogeneity of reported results was also assessed and examined. Only 4 out of 41 studies reported negative associations between ED and AUD. The magnitude of the associations between eating-disordered patterns and AUD ranged from small to medium size and were statistically significant for any ED, bulimia nervosa (BN)/bulimic behavior, purging, binge eating disorder (BED) and eating disorders not otherwise specified (EDNOS). No association was found between anorexia nervosa (AN) and AUD. The magnitude of the association between BN and AUD was the most divergent across studies and those between each of BED and dietary restriction and AUD were the most consistent across studies. Reported associations of different patterns of disordered eating and AUD were generally weakest and most divergent when participants were recruited from clinical settings and strongest and most homogeneous when participants were recruited from student populations.     

Personality and eating disorders: a decade in review

Personality traits have been implicated in the onset, symptomatic expression, and maintenance of eating disorders (EDs). The present article reviews literature examining the link between personality and EDs published within the past decade, and presents a meta-analysis evaluating the prevalence of personality disorders (PDs) in anorexia nervosa (AN), bulimia nervosa (BN), and binge eating disorder (BED) as assessed by self-report instruments versus diagnostic interviews. AN and BN are both consistently characterized by perfectionism, obsessive-compulsiveness, neuroticism, negative emotionality, harm avoidance, low self-directedness, low cooperativeness, and traits associated with avoidant PD. Consistent differences that emerge between ED groups are high constraint and persistence and low novelty seeking in AN and high impulsivity, sensation seeking, novelty seeking, and traits associated with borderline PD in BN. The meta-analysis, which found PD rates of 0 to 58% among individuals with AN and BN, documented that self-report instruments greatly overestimate the prevalence of every PD.     

51例进食障碍患者的临床特征分析

目的 :了解进食障碍患者的临床特征。方法 :对符合CCMD -2 -R神经性厌食症 (AN)和神经性贪食症 (BN)诊断标准的 5 1例住院进食障碍患者的临床特征进行了回顾性分析。结果 :AN和BN患者的怕胖心理、闭经、采取相似的方式减少食物对于身体的影响等临床相相似 (P >0 0 5 )。但是AN患者较BN患者发病年龄早 (t =2 3 2 0 ,P <0 0 5 ) ,体像障碍比较多见 (χ2 =6 110 ,P <0 0 5 ) ;BN患者的抑郁主诉多 (χ2 =8 612 ,P <0 0 0 1) ,病程长 (t=3 2 17,P <0 0 5 ) ,停工、停学时间长 (t=2 2 16,P <0 0 5 ) ,自知力较好。结论 :进食障碍两大综合征可能是一个疾病进程中的两个不同阶段 ,而贪食症的危害更应引起重视     

Mutation screen of the brain derived neurotrophic factor gene (BDNF): identification of several genetic variants and association studies in patients with obesity, eating disorders, and attention-deficit/hyperactivity disorder.

Several lines of evidence indicate an involvement of brain derived neurotrophic factor (BDNF) in body weight regulation and activity: heterozygous Bdnf knockout mice (Bdnf(+/-)) are hyperphagic, obese, and hyperactive; furthermore, central infusion of BDNF leads to severe, dose-dependent appetite suppression and weight loss in rats. We searched for the role of BDNF variants in obesity, eating disorders, and attention-deficit/hyperactivity disorder (ADHD). A mutation screen (SSCP and DHPLC) of the translated region of BDNF in 183 extremely obese children and adolescents and 187 underweight students was performed. Additionally, we genotyped two common polymorphisms (rs6265: p.V66M; c.-46C > T) in 118 patients with anorexia nervosa, 80 patients with bulimia nervosa, 88 patients with ADHD, and 96 normal weight controls. Three rare variants (c.5C > T: p.T2I; c.273G > A; c.*137A > G) and the known polymorphism (p.V66M) were identified. A role of the I2 allele in the etiology of obesity cannot be excluded. We found no association between p.V66M or the additionally genotyped variant c.-46C > T and obesity, ADHD or eating disorders. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html.     

Differential motivational responses to food and pleasurable cues in anorexia and bulimia nervosa: a startle reflex paradigm

BACKGROUND: Abnormal perceptions of food and shape underpin the cognitive behavioural model of eating disorders (EDs). The aim of this study was to investigate motivational processing of disorder-specific and standard emotional cues in anorexia (AN) and bulimia nervosa (BN) using startle eyeblink modulation (SEM). SEM was used because it is sensitive to motivational states of approach (appetitive response) and withdrawal (aversive response), which are independent of conscious intentional control. METHOD: Acoustically elicited SEM and subjective anxiety ratings were measured in 30 female patients with an ED (n=15 AN, n=15 BN) and 30 female control subjects while they viewed ED-relevant stimuli (food, female bodies) and standardized emotional pictures. RESULTS: BN subjects showed an appetitive response (startle inhibition) to food relative to neutral cues that differed significantly from AN subjects. By contrast, self-reports indicated significantly increased anxiety related to food cues across both ED groups. To female body picture (relative to neutral) cues, no significant between-group differences were found for SEM. ED subjects unexpectedly showed an aversive response (startle potentiation) to positive cues, in contrast to controls, who showed the established startle attenuation. CONCLUSIONS: These preliminary results suggest that BN patients demonstrated an exaggerated appetitive response to food but not to standardized positive cues, whereas SEM in AN patients points to a generalized failure to activate the appetitive motivational system. Differences in motivational salience to food cues are in line with distinctions between AN and BN in eating behaviour and food consumption and support differential treatment requirements.     

5-HT2A receptor gene polymorphisms in anorexia nervosa and bulimia nervosa

To examine the distribution of different polymorphisms in genes of the 5-HT system in patients with anorexia nervosa (AN) and bulimia nervosa (BN), we analyzed the distribution of a polymorphism (-1438G/A) and the presence of known mutations in 5-HT2A and 5-HT2C receptor genes in 168 Italian female patients affected by AN and BN. Patients with AN restricting type (ANr) only, unlike those with AN binge eating/purging type (ANp) and BN purging type (BNp), showed a statistically significant difference in 5-HT2A-1438A/A genotype frequency with respect to controls. With regard to the other polymorphisms, no differences were found in the studied groups with respect to controls. 5-HT2A promoter polymorphism is probably implicated in the susceptibility to eating disorders and its involvement is more significant in ANr, when compared with ANp and BNp.     

Trajectories of interpersonal problems in residential eating disorder treatment: Exploring the influence of primary diagnosis

Baseline interpersonal problems have been associated with treatment outcome in eating disorders (ED) and are important for understanding ED maintenance and aetiology. Despite this evidence, little is known about trajectories of change in interpersonal problems in the context of treatment, particularly in intensive ED treatment. This study examined the trajectory of total interpersonal problems in residential ED treatment, as well as two subdomains previously highlighted in ED research of being overly Cold (interpersonally distant) or overly Domineering (interpersonally controlling), as a function of different primary presenting ED diagnoses: anorexia nervosa restricting subtype (AN-R), binge-purge subtype (AN-BP), and bulimia nervosa or binge eating (BN/BED). Interpersonal problem data were collected at admission, discharge, and 6-month follow-up. Trajectories were analysed with multilevel models. Results showed small-to-medium statistically significant reductions in interpersonal problems across diagnostic groups from admission to discharge for total interpersonal scores, and gains appeared to be maintained at follow-up for both AN groups. Patients diagnosed with primary AN experienced steeper declines in total interpersonal problems from admission to follow-up compared with patients diagnosed with BN/BED, with AN-R experiencing the steepest trajectory. Planned contrasts indicated anyone with relevant binge eating behaviours had higher average levels of both Cold, as well as Domineering problems. Exploratory contrasts suggested that patients who had more Domineering problems also exhibited more binge symptoms and were typically slower to improve. Overall, results suggest interpersonal problems are generally malleable in residential ED treatment, yet change patterns differ by presenting ED symptoms and interpersonal problem subdomain.     

Possible role of preproghrelin gene polymorphisms in susceptibility to bulimia nervosa.

Previous investigations have suggested that ghrelin, an endogenous orexigenic peptide, is involved in the pathology of eating disorders. We conducted a study to determine whether any preproghrelin gene polymorphisms are associated with eating disorders. Three hundred thirty-six eating disorder patients, including 131 anorexia nervosa (AN)-restricting types (AN-R), 97 AN-binge eating/purging types (AN-BP) and 108 bulimia nervosa (BN)-purging types (BN-P), and 300 healthy control subjects participated in the study. Genotyping was performed to determine the polymorphisms present, and with this information, linkage disequilibrium (LD) between the markers was analyzed and the distributions of the genotypes, the allele frequencies, and the haplotype frequencies were compared between the groups. The Leu72Met (408 C > A) (rs696217) polymorphism in exon 2 and the 3056 T > C (rs2075356) polymorphism in intron 2 were in LD (D' = 0.902, r2 = 0.454). Both polymorphisms were significantly associated with BN-P (allele-wise: P = 0.0410, odds ratio (OR) = 1.48; P = 0.0035, OR = 1.63, for Leu72Met and 3056 T > C, respectively). In addition, we observed a significant increase in the frequency of the haplotype Met72-3056C in BN-P patients (P = 0.0059, OR = 1.71). Our findings suggest that the Leu72Met (408 C > A) and the 3056 T > C polymorphisms of the preproghrelin gene are associated with susceptibility to BN-P.     

The 196G/A (val66met) polymorphism of the BDNF gene is significantly associated with binge eating behavior in women with bulimia nervosa or binge eating disorder

The brain-derived neurotrophic factor (BDNF) is involved not only in promoting neuronal outgrowth and differentiation, synaptic connectivity and neuronal repair, but also in modulating eating behavior. Since genetic factors likely contribute to the biological vulnerability to bulimia nervosa (BN) and binge eating disorder (BED), we investigated whether the functional 196G/A single nucleotide polymorphism (SNP) of the BDNF gene was associated to BN and/or BED or to some phenotypic aspects of the disordered eating. Two hundred and ten Caucasian women (126 with BN, 84 with BED and 121 healthy controls) participated into the study. No significant differences were found in the frequencies of the 196G/A variants of the BDNF gene among patients with BN or BED and healthy controls. In both BN and BED groups, subjects carrying the 196A/A genotype exhibited a weekly frequency of bingeing and a severity of binge eating (as assessed by the Bulimia Investigation Test Edinburgh) significantly higher than those with the 196A/G and 196G/G genotypes. These results suggest that the 196G/A SNP of the human BDNF gene does not contribute to the genetic susceptibility to BN and BED, but may predispose those patients to a more severe binge eating behavior.     

Association between serotonin transporter gene polymorphism and eating disorders outcome: a 6-year follow-up study

Eating disorder patients show different long-term outcomes, and trait-related alterations of serotonergic function, which might be related with the serotonin transporter (5-HTT) gene. We studied the relationships between 5-HTTLPR polymorphism, eating specific and general psychopathology and the long-term outcome of anorexia nervosa (AN) and bulimia nervosa (BN) patients. We evaluated the distribution of the functional 5-HTTLPR polymorphism in a series of 201 Italian, Caucasian, eating disorder patients (113 with AN and 88 with BN binge/purging (BP subtype) and in 150 Caucasian unrelated controls. Prior to starting an individual cognitive behavior therapy, a clinical assessment was performed by means of the structured clinical interview for DSM-IV axis I disorders and several self-report questionnaires. This assessment was repeated at the end of treatment, 3 years after the end of treatment and 3 years after the first follow-up. Diagnostic changes between AN and BN were frequent (28.3%), and the presence of depressive disorders was associated with a higher rate of diagnostic crossover during the follow-up period. The S-allele of the 5-HTTLPR genotype increases the risk susceptibility for both depressive comorbidity (OR?=?4.23; 95% CI, 1.45-12.37) and diagnostic crossover during the follow-up period in AN patients (OR = 5.04; 95% CI, 1.69-14.98). Logistic regression analyses confirmed these findings, when the interaction between genotype and psychiatric comorbidity as predictors of diagnostic instability in AN patients were taken into account. No significant association was found between 5-HTTLPR genotype and recovery. The S-allele of the 5-HTTLPR genotype increases the risk for depressive disorders comorbidity, and moderates the long-term outcome of anorectic patients.     

Family-based association study between brain-derived neurotrophic factor gene polymorphisms and attention deficit hyperactivity disorder in UK and Taiwanese samples.

Brain-derived neurotrophic factor (BDNF) plays an important role in normal neuronal development. Several lines of evidence implicate the involvement of BDNF in attention-deficit hyperactivity disorder (ADHD). This study investigated the role of two common BDNF variants (Val66Met, C270T) in two samples of ADHD probands from the United Kingdom (n = 180) and Taiwan (n = 212). We found evidence of increased transmission of the C allele of the C270T in Taiwanese samples (TDT: chi(2) = 6.78, P = 0.009) and the two samples pooled together (TDT: chi(2) = 7.24, P = 0.007). No association was found between the Val66Met polymorphism and ADHD in either of the two populations. Analysis of haplotypes demonstrated a significant decreased transmission of haplotypes containing the Val66 allele and the 270T allele in the Taiwanese samples (TDT: chi(2) = 4.57, P = 0.032) and the pooled sample set (TDT: chi(2) = 5.82, P = 0.016). This study provides evidence for the possible involvement of BDNF in susceptibility to ADHD.     

Childhood eating and weight in eating disorders: a multi-centre European study of affected women and their unaffected sisters

BACKGROUND: Previous studies have suggested that childhood eating and weight problems may be risk factors for eating disorders. Robust evidence is still lacking. AIMS: To investigate whether childhood eating and weight problems increase the risk of eating disorders in affected women compared to their unaffected sisters. METHODS: Women (150) with anorexia (AN) or bulimia nervosa (BN) recruited from clinical and community samples were compared to their unaffected sister closest in age on maternal reports of childhood eating and weight. RESULTS: Women with BN were significantly more overweight at the ages of 5 and 10 (both OR = 2.8, p < 0.01), ate a lot (OR = 1.3, p < 0.01), were less picky (OR = 0.6, p < 0.05) and ate quickly (OR = 2.3, p < 0.05) between the ages of 6 and 10 compared to their healthy sisters. Significantly more women with AN were described as having a higher weight at 6 months (OR = 0.8, p < 0.01) and 1 year (OR = 0.6, p < 0.01) compared to their healthy sisters. Childhood eating was comparable in the women with AN and their unaffected sisters. CONCLUSIONS: Traits of childhood overeating were more common in bulimic women compared to their unaffected siblings. Subjects with AN did not differ from their sisters on eating variables. The increased risk of BN due to childhood overweight suggests that prevention strategies for childhood obesity and overweight may therefore be applicable in BN.     

Association of NTRK3 and its interaction with NGF suggest an altered cross-regulation of the neurotrophin signaling pathway in eating disorders

Eating disorders (EDs) are complex psychiatric diseases that include anorexia nervosa and bulimia nervosa, and have higher than 50% heritability. Previous studies have found association of BDNF and NTRK2 to ED, while animal models suggest that other neurotrophin genes might also be involved in eating behavior. We have performed a family-based association study with 151 TagSNPs covering 10 neurotrophin signaling genes: NGFB, BDNF, NTRK1, NGFR/p75, NTF4/5, NTRK2, NTF3, NTRK3, CNTF and CNTFR in 371 ED trios of Spanish, French and German origin. Besides several nominal associations, we found a strong significant association after correcting for multiple testing (P = 1.04 x 10(-4)) between ED and rs7180942, located in the NTRK3 gene, which followed an overdominant model of inheritance. Interestingly, HapMap unrelated individuals carrying the rs7180942 risk genotypes for ED showed higher levels of expression of NTRK3 in lymphoblastoid cell lines. Furthermore, higher expression of the orthologous murine Ntrk3 gene was also detected in the hypothalamus of the anx/anx mouse model of anorexia. Finally, variants in NGFB gene appear to modify the risk conferred by the NTRK3 rs7180942 risk genotypes (P = 4.0 x 10(-5)) showing a synergistic epistatic interaction. The reported data, in addition to the previous reported findings for BDNF and NTRK2, point neurotrophin signaling genes as key regulators of eating behavior and their altered cross-regulation as susceptibility factors for EDs.     

Neurobiology of anorexia and bulimia nervosa

Anorexia nervosa (AN) and bulimia nervosa (BN) are related disorders of unknown etiology that most commonly begin during adolescence in women. AN and BN have unique and puzzling symptoms, such as restricted eating or binge-purge behaviors, body image distortions, denial of emaciation, and resistance to treatment. These are often chronic and relapsing disorders, and AN has the highest death rate of any psychiatric disorder. The lack of understanding of the pathogenesis of this illness has hindered the development of effective interventions, particularly for AN. Individuals with AN and BN are consistently characterized by perfectionism, obsessive-compulsiveness, and dysphoric mood. Individuals with AN tend to have high constraint, constriction of affect and emotional expressiveness, ahendonia and asceticism, whereas individuals with BN tend to be more impulsive and sensation seeking. Such symptoms often begin in childhood, before the onset of an eating disorder, and persist after recovery, suggesting they are traits that create a vulnerability for developing an ED. There is growing acknowledgement that neurobiological vulnerabilities make a substantial contribution to the pathogenesis of AN and BN. Considerable evidence suggests that altered brain serotonin (5-HT) function contributes to dysregulation of appetite, mood, and impulse control in AN and BN. Brain imaging studies, using 5-HT specific ligands, show that disturbances of 5-HT function occur when people are ill, and persist after recovery from AN and BN. It is possible that a trait-related disturbance of 5-HT neuronal modulation predates the onset of AN and contributes to premorbid symptoms of anxiety, obsessionality, and inhibition. This dysphoric temperament may involve an inherent dysregulation of emotional and reward pathways which also mediate the hedonic aspects of feeding, thus making these individuals vulnerable to disturbed appetitive behaviors. Restricting food intake may become powerfully reinforcing because it provides a temporary respite from dysphoric mood. Several factors may act on these vulnerabilities to cause AN to start in adolescence. First, puberty-related female gonadal steroids or age-related changes may exacerbate 5-HT dysregulation. Second, stress and/or cultural and societal pressures may contribute by increasing anxious and obsessional temperament. Individuals with AN may discover that reduced dietary intake, by reducing plasma tryptophan availability, is a means by which they can modulate brain 5-HT functional activity and anxious mood. People with AN enter a vicious cycle which accounts for the chronicity of this disorder because caloric restriction results in a brief respite from dysphoric mood. However, malnutrition and weight loss, in turn, produce alterations in many neuropeptides and monoamine function, perhaps in the service of conserving energy, but which also exaggerates dysphoric mood. In summary, this article reviews findings in brain chemistry and neuroimaging that shed new light on understanding the psychopathology of these difficult and frustrating disorders.     

Polymorphisms within the promoter and the intron 2 of the serotonin transporter gene in a population of bulimic patients

The serotonin transporter (5-HTT) gene is a firm candidate to explain eating disorders. In this association study, two different polymorphisms were analysed: a variable number of tandem repeat (VNTR) polymorphism in intron 2 and a deletion/insertion polymorphism (5-HTTLPR) in the promoter region. The hypothesis that these gene polymorphisms may be a susceptibility factor in bulimia nervosa (BN) was explored in a female population of 102 purgative bulimics. BN patients who have suffered preceding anorexia nervosa (AN) episodes formed the so-called previous AN bulimic patient group. In our sample of normal-eater controls and purging type bulimics, regardless of whether or not the BN patients had suffered prior AN episodes, no differences were found considering the frequencies of genotypes, alleles or haplotypes of both polymorphic regions of the 5-HTT gene.     

Serotonin transporter regulatory region polymorphism is associated with anorexia nervosa.

Several lines of evidence support possible serotonin transporter (5-HTT) involvement in modulating eating disorders (ED). The 5-HTT gene is a good candidate for genetic studies on the course of ED, despite controversy concerning the association between polymorphism in the 5-HTT gene promoter region (5-HTTLPR) and ED. Comparison of 5-HTTLPR distribution in 195 female Japanese ED patients and 290 age- and gender-matched control subjects facilitated examining the association between the course of the disease and 5-HTTLPR in 138 of 195 ED subjects. The 5-HTTLPR S allele frequency was significantly higher in subjects with anorexia nervosa (AN) than in control subjects. Among subjects observed > or =3 years, the S allele frequency was significantly higher in those diagnosed as AN at ED onset than in those diagnosed as AN in this study. The 5-HTTLPR S allele might play some role in the development of AN with persistent disease.