Lucia Fernandez-Novoa
Head of the Department of Molecular Genetics , Madrid Spain
Title: A genomic approach to histamine function
Biography
Biography: Lucia Fernandez-Novoa
Abstract
Histamine, is an ancestral biogenic amine present in many living tissues as a normal constituent of the body with multiple effects in several organs of mammals and invertebrates. Histamine exerts its effects on target cells through 4 different types of receptors: H1, H2, H3 and H4. Genetic variation in histamine receptors and histamine-synthesizing and -metabolizing enzymes is associated with differences in histamine metabolism, altered enzyme activities, and risk of disease.
To advance in the knowledge of histamine genomics, we analysed 3 genetic polymorphisms in the H1 receptor gene (rs901865), the H2 receptor gene (rs2067474) and the HNMT gene (rs11558538) in 195 patients, to establish a potential association between these polymorphisms and blood histamine levels, serum levels of Igs, PCR-us, TNF, and several ILs, as well as blood cells count.
The results showed an association with serum TNF levels and monocyte count for the HRH1 gene polymorphism. Subjects with genotype GG have increased serum TNF and monocyte count comparing with subjects with genotype GA+AA. There are more subjects with abnormal serum TNF levels and genotype GG, than with genotype GA+AA. The HRH2 gene polymorphism is associated with pathological PCR-us levels. Subjects with genotype GA presented abnormal values of serum PCR-us comparing to subjects with genotype GG. The HNMT polymorphism showed an association with serum IL8 levels. Individuals with genotype CC have increased levels of IL8 in comparison with individuals with genotype CT.
The results of this study indicate that HA-related polymorphisms participate in the modulation of the immune-inflammatory response.