7 research outputs found
Study of the serotonin transporter (SLC6A4) and BDNF genes in French patients with non syndromic mental deficiency
<p>Abstract</p> <p>Background</p> <p>Mental deficiency has been linked to abnormalities in cortical neuronal network connectivity and plasticity. These mechanisms are in part under the control of two interacting signalling pathways, the serotonergic and the brain-derived neurotrophic (BDNF) pathways. The aim of the current paper is to determine whether particular alleles or genotypes of two crucial genes of these systems, the serotonin transporter gene (<it>SLC6A4</it>) and the brain-derived neurotrophic factor gene (<it>BDNF</it>), are associated with mental deficiency (MD).</p> <p>Methods</p> <p>We analyzed four functional polymorphisms (rs25531, 5-HTTLPR, VNTR, rs3813034) of the <it>SLC6A4 </it>gene and one functional polymorphism (Val66 Met) of the <it>BDNF </it>gene in 98 patients with non-syndromic mental deficiency (NS-MD) and in an ethnically matched control population of 251 individuals.</p> <p>Results</p> <p>We found no significant differences in allele and genotype frequencies in the five polymorphisms studied in the <it>SLC6A4 </it>and <it>BDNF </it>genes of NS-MD patients versus control patients. While the comparison of the patterns of linkage disequilibrium (D') in the control and NS-MD populations revealed a degree of variability it did not, however, reach significance. No significant differences in frequencies of haplotypes and genotypes for VNTR/rs3813034 and rs25531/5-HTTLPR were observed.</p> <p>Conclusion</p> <p>Altogether, results from the present study do not support a role for any of the five functional polymorphisms of <it>SLC6A4 </it>and <it>BDNF </it>genes in the aetiology of NS-RM. Moreover, they suggest no epistatic interaction in NS-MD between polymorphisms in <it>BDNF </it>and <it>SLC6A4</it>. However, we suggest that further studies on these two pathways in NS-MD remain necessary.</p
Xq27 FRAXA locus is a strong candidate for dyslexia: evidence from a genome-wide scan in French families.
Dyslexia is a frequent neurodevelopmental
learning disorder. To date, nine susceptibility loci have
been identified, one of them being DYX9, located in Xq27.
We performed the first French SNP linkage study followed
by candidate gene investigation in dyslexia by studying 12
multiplex families (58 subjects) with at least two children
affected, according to categorical restrictive criteria for
phenotype definition. Significant results emerged on
Xq27.3 within DYX9. The maximum multipoint LOD
score reached 3,884 between rs12558359 and rs454992.
Within this region, seven candidate genes were investigated
for mutations in exonic sequences (CXORF1,
CXORF51, SLITRK2, FMR1, FMR2, ASFMR1, FMR1NB),
all having a role during brain development. We further
looked for 50
UTR trinucleotide repeats in FMR1 and FMR2
genes. No mutation or polymorphism co-segregating with
dyslexia was found. This finding in French families with
Dyslexia showed significant linkage on Xq27.3 enclosing
FRAXA, and consequently confirmed the DYX9 region as
a robust susceptibility locus. We reduced the previously
described interval from 6.8 (DXS1227–DXS8091) to 4 Mb
also disclosing a higher LOD score
Conception, synthèse et évaluation biologique d’inhibiteurs de LIM kinases
National audienc
LIM kinases as new therapeutic targets for the treatment of neurofibromatosis type 1
International audienc