The inflammatory bowel diseases (IBD) are common, complex disorders in which genetic and environmental factors are believed to interact leading to chronic inflammatory responses against the gut ...microbiota. Earlier genetic studies performed in mostly adult population of European descent identified 163 loci affecting IBD risk, but most have relatively modest effect sizes, and altogether explain only ~20% of the genetic susceptibility. Pediatric onset represents about 25% of overall incident cases in IBD, characterized by distinct disease physiology, course and risks. The goal of this study is to compare the allelic architecture of early onset IBD with adult onset in population of European descent.
We performed a fine mapping association study of early onset IBD using high-density Immunochip genotyping on 1008 pediatric-onset IBD cases (801 Crohn's disease; 121 ulcerative colitis and 86 IBD undetermined) and 1633 healthy controls. Of the 158 SNP genotypes obtained (out of the 163 identified in adult onset), this study replicated 4% (5 SNPs out of 136) of the SNPs identified in the Crohn's disease (CD) cases and 0.8% (1 SNP out of 128) in the ulcerative colitis (UC) cases. Replicated SNPs implicated the well known NOD2 and IL23R. The point estimate for the odds ratio (ORs) for NOD2 was above and outside the confidence intervals reported in adult onset. A polygenic liability score weakly predicted the age of onset for a larger collection of CD cases (p< 0.03, R2= 0.007), but not for the smaller number of UC cases.
The allelic architecture of common susceptibility variants for early onset IBD is similar to that of adult onset. This immunochip genotyping study failed to identify additional common variants that may explain the distinct phenotype that characterize early onset IBD. A comprehensive dissection of genetic loci is necessary to further characterize the genetic architecture of early onset IBD.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Background Several copy number variants (CNVs) have been implicated as susceptibility factors for schizophrenia (SZ). Some of these same CNVs also increase risk for autism spectrum disorders, ...suggesting an etiologic overlap between these conditions. Recently, de novo duplications of a region on chromosome 7q11.23 were associated with autism spectrum disorders. The reciprocal deletion of this region causes Williams-Beuren syndrome. Methods We assayed an Ashkenazi Jewish cohort of 554 SZ cases and 1014 controls for genome-wide CNV. An excess of large rare and de novo CNVs were observed, including a 1.4 Mb duplication on chromosome 7q11.23 identified in two unrelated patients. To test whether this 7q11.23 duplication is also associated with SZ, we obtained data for 14,387 SZ cases and 28,139 controls from seven additional studies with high-resolution genome-wide CNV detection. We performed a meta-analysis, correcting for study population of origin, to assess whether the duplication is associated with SZ. Results We found duplications at 7q11.23 in 11 of 14,387 SZ cases with only 1 in 28,139 control subjects (unadjusted odds ratio 21.52, 95% confidence interval: 3.13–922.6, p value 5.5 × 10−5 ; adjusted odds ratio 10.8, 95% confidence interval: 1.46–79.62, p value .007). Of three SZ duplication carriers with detailed retrospective data, all showed social anxiety and language delay premorbid to SZ onset, consistent with both human studies and animal models of the 7q11.23 duplication. Conclusions We have identified a new CNV associated with SZ. Reciprocal duplication of the Williams-Beuren syndrome deletion at chromosome 7q11.23 confers an approximately tenfold increase in risk for SZ.
The rapid exocytosis of von Willebrand factor (VWF) in response to vascular injury can be attributed to the fact that VWF is stored in the Weibel-Palade bodies (WPBs) of endothelial cells. We ...describe a system for examining the ability of VWF to drive both the formation of a storage compartment and the function of that compartment with respect to regulated secretion. Transient transfection of HEK293 cells with wild-type human VWF cDNA leads to the formation of numerous elongated organelles that resemble WPBs. These “pseudo-WPBs” exhibit the internal structure, as well as the ability to recruit membrane proteins including P-selectin, of bona fide WPBs. Finally, VWF was efficiently secreted upon stimulation by phorbol ester. We used this system to examine 3 VWF mutations leading to von Willebrand disease that affect VWF multimerization and constitutive secretion. Surprisingly we find that all 3 mutants can, to some extent, make pseudo-WPBs that recruit appropriate membrane proteins and that are responsive to secretagogues. The most striking defects are a delay in formation and a reduction in the length and number of pseudo-WPBs in proportion to the clinical severity of the mutation. Studies of pseudo-WPB formation in this system thus yield insights into the structure-function relationships underpinning the ability of VWF to form functional WPBs. (Blood. 2003;102:2452-2458)
Duarte galactosemia is a mild to asymptomatic condition that results from partial impairment of galactose-1-phosphate uridylyltransferase (GALT). Patients with Duarte galactosemia demonstrate reduced ...GALT activity and carry one profoundly impaired GALT allele (G) along with a second, partially impaired GALT allele (Duarte-2, D2). Molecular studies reveal at least five sequence changes on D2 alleles: a p.N314D missense substitution, three intronic base changes and a 4 bp deletion in the 5′ proximal sequence. The four non-coding sequence changes are unique to D2. The p.N314D substitution, however, is not; it is found together with a silent polymorphism, p.L218(TTA), on functionally normal Duarte-1 alleles (D1, also called Los Angeles or LA alleles). The HapMap database reveals that p.N314D is a common human variant, and cross-species comparisons implicate D314 as the ancestral allele. The p.N314D substitution is also functionally neutral in mammalian cell and yeast expression studies. In contrast, the 4 bp 5′ deletion characteristic of D2 alleles appears to be functionally impaired in reporter gene transfection studies. Here we present allele-specific qRT–PCR evidence that D2 alleles express less mRNA in vivo than their wild-type counterparts; the difference is small but statistically significant. Furthermore, we characterize the prevalence of the 4 bp deletion in GG, NN and DG populations; the deletion appears exclusive to D2 alleles. Combined, these data strongly implicate the 4 bp 5′ deletion as a causal mutation in Duarte galactosemia and suggest that direct tests for this deletion, as proposed here, could enhance or supplant current tests, which define D2 alleles on the basis of the presence and absence of linked coding sequence polymorphisms.
Blockade of the CD154–CD40 co-stimulatory pathway with anti-CD154 mAbs has shown impressive efficacy in models of autoimmunity and allotransplantation. Clinical benefit was also demonstrated in ...systemic lupus erythematosus (SLE) and idiopathic thrombocytopenia patients with the humanized anti-CD154 mAb, 5C8 (hu5C8). However, thromboembolic complications that occurred during the course of the hu5C8 clinical trials have proven to be a major setback to the field and safe alternative therapeutics targeting the CD154–CD40 pathway are of great interest. Recently, effector mechanisms have been shown to play a part in anti-CD154 mAb-induced transplant acceptance in murine models, while this issue remains unresolved for humoral-mediated models. Herein, aglycosyl anti-CD154 mAbs with reduced binding to FcγR and complement were used as a novel means to test the role of effector mechanisms in non-human primate and murine models not amenable to gene knockout technology. While aglycosyl hu5C8 mAb was relatively ineffective in rhesus renal and islet allotransplantation, it inhibited primary and secondary humoral responses to a protein immunogen in cynomolgus monkeys. Moreover, an aglycosyl, chimeric MR1 mAb (muMR1) prolonged survival and inhibited pathogenic auto-antibody production in a murine model of SLE. Thus, the mechanisms required for efficacy of anti-CD154 mAbs depend on the nature of the immune challenge.
Processing resyllabified words in French Spinelli, Elsa; McQueen, James M; Cutler, Anne
Journal of memory and language,
02/2003, Letnik:
48, Številka:
2
Journal Article
Recenzirano
Odprti dostop
In French, the final
▪ of
dernier is not pronounced in
dernier train (last train), but is pronounced, in the following syllable, in a liaison environment like
dernier oignon (last onion). Due to ...liaison,
dernier oignon becomes homophonous with
dernier rognon (last kidney). In four pairs of cross-modal priming experiments, French participants made visual lexical decisions to vowel- or consonant-initial targets (e.g.,
oignon,
rognon) following both versions of spoken sentences like
C’est le dernier oignon/
rognon. Facilitation was found for both types of target when targets matched the speaker’s intended segmentation, but was weaker when they mismatched the intended segmentation. In unambiguous sentences there was facilitation only for targets matching the speaker’s intentions. The consonants in the liaison environments were shorter than the word-initial consonants (e.g.,
▪ in
dernier oignon vs.
rognon). Word recognition therefore appears to be influenced by subphonemic cues to the words that speakers intend.