Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004352 (autism)
 32,579 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Monoamine oxidase A (MAOA) is an enzyme expressed in the brain that metabolizes dopamine, norepinephrine, epinephrine, and serotonin. Abnormalities of serotonin neurotransmission have long been implicated in the psychopathology of autism. A polymorphism exists within the promoter region of the MAOA gene that influences MAOA expression levels so that "low activity" alleles are associated with increased neurotransmitter levels in the brain. Individuals with autism often exhibit elevated serotonin levels. Additional studies indicate that the "low activity" allele may be associated with lower IQ and more severe autistic symptoms. In this study we genotyped the MAOA promoter polymorphism in a group of 29 males (age 2-3 years) with autism and a group of 39 healthy pediatric controls for whom brain MRI data was available. We found a consistent association between the "low activity" allele and larger brain volumes for regions of the cortex in children with autism but not in controls. We did not find evidence for over-transmission of the "low activity" allele in a separate sample of 114 affected sib pair families. Nor did we find any unknown SNPs in yet another sample of 96 probands. Future studies will determine if there is a more severe clinical phenotype associated with both the "low activity" genotype and the larger brain volumes in our sample.
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PMID:Cortical enlargement in autism is associated with a functional VNTR in the monoamine oxidase A gene. 1836 46

Monoamine oxidase A gene (MAOA) has been thought to be a candidate gene implicated in autism spectrum disorder (ASD). This study evaluates the relationship between ASDs and MAOA markers (i.e., uVNTR and four single nucleotide polymorphisms (SNPs)) in 151 Korean family trios with children diagnosed with ASDs, and 193 unrelated Korean controls. The result of case-control global haplotype analysis also showed a statistically significant difference in haplotype frequencies between ASD patients and controls (male d.f.=5, p<0.001; female d.f.=7, p<0.001). With the specific haplotype analyses, the frequencies of the most frequent haplotype (AGG) with three SNPs (rs5906883+rs1137070+rs3027407) in ASD showed significant statistical differences between ASD patients and controls in both the male and female groups (d.f.=1, male p=0.001, female p<0.001). In a family-based association test (FBAT) analysis, it was observed that, in the dominant model, a three-repeat allele of a MAOA-uVNTR marker was preferentially transmitted in ASDs (Z=2.213, p=0.027). Moreover, in the global haplotype analysis, the statistically significant evidence of associations with ASD were demonstrated in additive and dominant models (additive chi(2)=11.349, d.f.=2, p=0.003; dominant chi(2)=6.198, d.f.=2, p=0.045).
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PMID:Family- and population-based association studies of monoamine oxidase A and autism spectrum disorders in Korean. 1910 Jul 89

Monoamine oxidase A (MAO A), encoded by the X chromosome, catalyzes the oxidative deamination of monoamine neurotransmitters, such as serotonin, and plays a critically important role in brain development and functions. Abnormal MAO A activity has been implicated in several neuropsychiatric disorders, such as depression, autism, and attention deficit hyperactivity disorder, which show sexual dimorphism. However, the molecular basis for these disease processes is unclear. Recently, we found that MAO A was a putative target gene directly regulated by a transcription factor encoded by the sex-determining region Y (SRY) gene located on the Y chromosome. We demonstrated that SRY activates both MAO A-promoter and catalytic activities in a human male neuroblastoma BE(2)C cell line. A functional SRY-binding site in the MAO A core promoter was identified and validated by electrophoretic mobility shift and chromatin immunoprecipitation (ChIP) analyses. Coimmunoprecipitation and ChIP assays showed that SRY and Sp1 form a transcriptional complex and synergistically activate MAO A transcription. This is the first study demonstrating that the Y-encoded transcription factor SRY is capable of regulating an X-located gene, suggesting a novel molecular mechanism for sexual dimorphism in neural development, brain functions, and initiation/progression of neural disorders associated with MAO A dysfunction.
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PMID:Regulation of monoamine oxidase A by the SRY gene on the Y chromosome. 1966 Dec 85