No abstract

The purpose of this study was to evaluate the relationship between attention deficit hyperactivity disorder (ADHD) and polymorphism of the two regions of the 5-HTT gene [variable number of tandem repeats (VNTR) and 5-HTTLRR] in a sample of Turkish children. Using the PCR technique, these polymorphisms were assessed in 71 patients with ADHD and 128 healthy controls. The 5-HTTLPR S/S genotype was significantly lower in the patients than in the controls (p = 0.018). Homozygous and heterozygous L variant predominated in the ADHD group. But the VNTR STin2.12/12 genotype was significantly less found in the patients than in the controls (p = 0.001). There was no significant difference between the frequency of the short (S), long, 10, and 12 alleles of both groups. The lack of an S/S variant of 5-HTTLPR polymorphism of the STin2.12/12 variant of VNTR polymorphism appears to be associated with an increased risk of ADHD.

Serotonin (5-HT) is a key neurotransmitter in the central nervous system. It is suggested that serotonergic dysfunction may be involved in the pathophysiology of fibromyalgia syndrome (FS). In this study, we aimed to investigate T102C polymorphism of the 5-HT2A receptor gene in FS. Fifty-eight patients with FS and 58 unrelated healthy volunteer controls were included in the study. In both groups, the C/C, C/T, and T/T genotypes of the 5-HT gene were represented in 31% (22.4% in controls), 50% (53.4%), and 19% (24.1%), respectively. The 5-HT2A receptor gene polymorphism results were not significantly different between patients and controls (chi squared test, P>0.05). There was a significant correlation between patients with the T/T genotype and the subgroup according to the SCL-90-R test, (analysis of variance, P<0.05). We also saw that patients with the T/T genotype had the lowest pain threshold. CONCLUSION. T102C polymorphism of the 5-HT2A receptor gene is not associated with the etiology of FS. Our results also indicate that the T/T genotype may be responsible for psychiatric symptoms of FS.

Our results suggest that the presence of the I allele may confer susceptibility to development of psoriasis in individuals from psoriatic families.

Gestational nicotine treatment induces marked changes in the organisation of the developing retina in newborn rats histopathologically. Quantitative morphometric analysis clearly demonstrated that the two most affected structures were the retinal ganglion cells and the inner plexiform layer, both of which are supplied by central retinal artery.