Anàlisi mutacional i estudi d'associació del gen receptor domini discoidina 1 (ddr1) en l'esquizofrènia.

Resumo

The aim with this thesis has been to assess the association between the DDR1 gene and schizophrenia and the necessary tools to identify and score SNPs. In the first study, a mutational screening of the coding and exon-intron sequences of DDR1 was performed in 100 samples of schizophrenic patients using the sequencing approach of pooled DNA. A total of 17 genetic variants were identified: 16 SNPs and a deletion of 2 bp. In the second study, a population association and linkage disequilibrium (LD) analyses were carried out on 297 patients and 298 controls of Spanish origin for 5 SNPs within DDR1 region. Significant differences were observed between the haplotype distribution between patients and controls (p=0.002, 500 permutations, Phase). No significant differences were observed in allele and genotype frequencies between groups of study. In addition, pair-wise LD showed that all five SNPs were highly linked with D values higher than 0.8, except for the N502S variant in the patient group (D values ranging from 0.17 to 0.72). The potential for population stratification artifact was evaluted by genotyping a set of 25 unlinked markers. Formal testing showed that population structure did not explain the findings. Although no direct correlation was found between the allelic combinations and schizophrenia, it can not be ruled out that other genetic variants in DDR1 or flanking regions could be involved in the disease. In the third study, a new approach for multiplex SNP analysis combining the eTag System with the Invader(r) method was evaluated. A total of 10 SNPs were analyzed in 540 samples using both the eTag Multiplex Invader Assay and the conventional assay PCR-RFLP to measure genotyping accuracy and reproducibility. The typing concordance between both methods was 100%. This is the first study that demonstrates that the method eTag Multiplex Invader SNP Assay is a valid approach for SNP scoring.