Is there a role for rare variants in DRD4 gene in the susceptibility for ADHD Searching for an effect of allelic heterogeneity
- Authors: Tovo-Rodrigues, Luciana , Rohde, Luis , Roman, Tatiana , Schmitz, Marcelo , Polanczyk, Guilherme , Zeni, Cristian , Marques, Francine , Contini, Veronica , Grevet, Eugenio , Belmonte-De-Abreu, Paulo , Bau, Claiton , Hutz, Mara
- Date: 2012
- Type: Text , Journal article
- Relation: Molecular Psychiatry Vol. 17, no. 5 (May 2012), p. 520-526
- Full Text: false
- Reviewed:
- Description: Although several studies have demonstrated an association between the 7-repeat (7R) allele in the 48-bp variable number of tandem repeats (VNTRs) in the exon 3 at dopamine receptor D4 (DRD4) gene and attention-deficit/ hyperactivity disorder (ADHD), others failed to replicate this finding. In this study, a total of 786 individuals with ADHD were genotyped for DRD4 exon 3 VNTR. All 7R homozygous subjects were selected for VNTR re-sequencing. Subjects homozygous for the 4R allele were selected paired by age, ancestry and disorder subtypes in order to have a sample as homogeneous as possible with 7R/7R individuals. Using these criteria, 103 individuals (66 with ADHD and 37 control individuals) were further investigated. An excess of rare variants were observed in the 7R alleles of ADHD patient when compared with controls (P = 0.031). This difference was not observed in 4R allele. Furthermore, nucleotide changes that predict synonymous and non-synonymous substitutions were more common in the 7R sample (P = 0.008 for total substitutions and P = 0.043 for non-synonymous substitutions). In silico prediction of structural/functional alterations caused by these variants have also been observed. Our findings suggest that not only repeat length but also DNA sequence should be assessed to better understand the role of DRD4 exon 3 VNTR in ADHD genetic susceptibility.
- Description: C1
Pathway analysis shows association between FGFBP1 and hypertension
- Authors: Tomaszewski, Maciej , Charchar, Fadi , Nelson, Christopher , Barnes, Timothy , Denniff, Matthew , Kaiser, Michael , Debiec, Radoslaw , Christofidou, Paraskevi , Rafelt, Suzanne , Van Harst, Pim Der , Wang, William , Maric, Christine , Zukowska-Szczechowska, Ewa , Samani, Nilesh
- Date: 2011
- Type: Text , Journal article
- Relation: Journal of the American Society of Nephrology Vol. 22, no. 5 (2011), p. 947-955
- Full Text: false
- Reviewed:
- Description: Variants in the gene encoding fibroblast growth factor 1 (FGF1) co-segregate with familial susceptibility to hypertension, and glomerular upregulation of FGF1 associates with hypertension. To investigate whether variants in other members of the FGF signaling pathway may also associate with hypertension, we genotyped 629 subjects from 207 Polish families with hypertension for 79 single nucleotide polymorphisms in eight genes of this network. Family-based analysis showed that parents transmitted the major allele of the rs16892645 polymorphism in the gene encoding FGF binding protein 1 (FGFBP1) to hypertensive offspring more frequently than expected by chance (P = 0.005). An independent cohort of 807 unrelated Polish subjects validated this association. Furthermore, compared with normotensive subjects, hypertensive subjects had approximately 1.5- and 1.4-fold higher expression of renal FGFBP1 mRNA and protein (P = 0.04 and P = 0.001), respectively. By immunohistochemistry, hypertensionrelated upregulation of FGFBP1 was most apparent in the glomerulus and juxtaglomerular space. Taken together, these data suggest that FGFBP1 associates with hypertension and that systematic analysis of signaling pathways can identify previously undescribed genetic associations. Copyright © 2011 by the American Society of Nephrology.