Associations of Mitochondrial Haplogroups B4 and E with Biliary Atresia and Differential Susceptibility to Hydrophobic Bile Acid

Mitochondrial dysfunction has been implicated in the pathogenesis of biliary atresia (BA). This study aimed to determine whether a specific mitochondrial DNA haplogroup is implicated in the pathogenesis and prognosis of BA. We determined 40 mitochondrial single nucleotide polymorphisms in 15 major mitochondrial haplogroups by the use of 24-plex PCR and fluorescent beads combined with sequence-specific oligonucleotide probes in 71 patients with BA and in 200 controls in the Taiwanese population of ethnic Chinese background. The haplogroup B4 and E prevalence were significantly lower and higher respectively, in the patients with BA than in the controls (odds ratios, 0.82 [p = 0.007] and 7.36 [p = 0.032] respectively) in multivariate logistic-regression analysis. The 3-year survival rate with native liver was significantly lower in haplogroup E than the other haplogroups (P = 0.037). A cytoplasmic hybrid (cybrid) was obtained from human 143B osteosarcoma cells devoid of mtDNA (ρ⁰ cell) and was fused with specific mtDNA bearing E and B4 haplogroups donated by healthy Taiwanese subjects. Chenodeoxycholic acid treatment resulted in significantly lower free radical production, higher mitochondrial membrane potential, more viable cells, and fewer apoptotic cybrid B4 cells than parental 143B and cybrid E cells. Bile acid treatment resulted in a significantly greater protective mitochondrial reaction with significantly higher mitochondrial DNA copy number and mitofusin 1 and 2 concentrations in cybrid B4 and parental cells than in cybrid E cells. The results of the study suggested that the specific mitochondrial DNA haplogroups B4 and E were not only associated with lower and higher prevalence of BA respectively, in the study population, but also with differential susceptibility to hydrophobic bile acid in the cybrid harboring different haplogroups.     

<Emphasis Type="Italic">IL4</Emphasis> in the 5q31 context: association studies of type 1 diabetes and rheumatoid arthritis in the Spanish population

IL4, the gene coding the prototypic Th2 cytokine, has been frequently studied in the context of several inflammatory conditions, but conclusive results have not been obtained. This gene is located in the 5q31-33 complex genetic region, which shows some susceptibility factors to type 1 diabetes (T1D) and rheumatoid arthritis (RA) among other inflammatory conditions. Our aim was to assess the involvement on T1D and RA of IL4 polymorphisms considered individually and in combination with other polymorphisms in 5q31-33, specifically in the OCTN locus, where the L503F polymorphism has been associated with Crohn's disease and other Th1 diseases. We performed a case-control study including 316 T1D patients, 599 RA patients and 540 healthy controls, all of them corresponding to white Spanish individuals. The IL4 single-nucleotide polymorphisms (SNPs) -590C/T (rs2243250) and the OCTN1 exonic SNP L503F (rs1050152) were analysed in all samples. Frequency comparisons of -590C/T and stratified analysis including both cited SNPs were performed using chi-square tests. The -590C/T IL4 SNP was not found associated with T1D or RA when individual analyses were performed. However, a significant association with T1D emerged after stratification by L503F [p=0.02, odds ratio=1.95, 95% CI=1.07-3.55]. The location of the IL4 gene in the complex 5q31-33 genetic region, which contains many genes involved in immunological responses and presents linkage disequilibrium extended along many kilobases, makes necessary to interpret cautiously the previous IL4-association studies.     

Polymorphisms of TNFalpha, IL1beta, and IL1RN genes in chronic obstructive pulmonary disease

It is recognized that genetic factors play a role in the susceptibility to COPD. COPD is characterized by airflow limitation. Chronic inflammation causes small airway disease and parenchymal destruction, leading to the airflow limitation. Polymorphisms in pro-inflammatory cytokine genes may confer a risk for the development of COPD. A case-control association study was performed in Japanese population (88 COPD patients and 61 controls) and Egyptian population (106 patients and 72 controls). Genotype and allele frequencies of the TNFalpha -308 G/A and +489 G/A polymorphisms, the IL1beta -511 C/T, -31 T/C, and +3954 C/T polymorphisms, and a VNTR polymorphism in intron 2 of the IL1RN gene were investigated. In addition, pairwise haplotype frequencies were analyzed. When studied independently, none of the polymorphisms were associated with the development of COPD in both populations. However, in the Egyptian population, the distributions of the haplotype (IL1beta -31 T/C : IL1beta +3954 C/T) were significantly different between the COPD patients and the controls (p(corr)=0.0037). Our findings suggest that this haplotype within the IL1beta gene may be involved in the pathogenesis of COPD and that the genetic factors of COPD susceptibility might be different between different populations.     

Association between genes encoding components of the IL-4/IL-4 receptor pathway and dermatitis in children

Objective

To determine whether IL-4, IL-4Rα and STAT6 polymorphisms are associated with susceptibility to dermatitis in Egyptian children.

Methods

We genotyped three groups of children, consisting of 106 atopic dermatitis (AD) children, 95 non-AD children, and 100 of healthy controls, for IL-4 (− 590 C/T), (− 33 C/T), IL-4Rα (I50V), (Q576R) and STAT6 (2964 G/A), (2892 C/T) gene polymorphisms using PCR-RFLP assay. Total serum IgE and serum IL-4 levels were detected by ELISA.

Results

There was a non-significant association of IL-4 − 590 C/T, − 33 C/T polymorphisms in the children with non-AD or those with AD when compared with the controls. We identified a significant association between IL-4Rα I50V, Q576R polymorphisms and dermatitis susceptibility in AD (p = 0.002, < 0.001 respectively), whereas no such association was observed in non-AD group (p = 0.52, 0.99 respectively). A significant association between STAT6 polymorphisms and both types of dermatitis was found. Patients who were carriers of IL4 − 590C, IL-4Rα I50V G, STAT6 2964 A and STAT6 2892 T had an increased risk of AD [OR and 95% CI: 3.2 (2.5–4.2), p = 0.005]. Furthermore, there was no relation between each polymorphism and serum IL-4 level (p > 0.05 for each) while homozygosity for the risk alleles of IL-4, IL-4Rα and STAT6 SNPs were significantly associated with increased total IgE levels in all subjects.

Conclusion

In Egyptian children, the IL-4Rα and the STAT6 polymorphism may play a role in susceptibility to AD. In addition, gene–gene interaction between the IL-4, the IL-4Rα and the STAT6 significantly increases an individual's susceptibility to AD.     

Association study of interleukin-4 polymorphisms with paranoid schizophrenia in the Polish population: a critical approach

Changes in immunological system are one of dysfunctions reported in schizophrenia. Some changes based on an imbalance between Th1 and Th2 cytokines results from cytokine gene polymorphisms. Interleukin-4 gene (IL4) is considered as a potential candidate gene in schizophrenia association studies. The aim of the current case-control study was to examine whether the -590C/T (rs2243250) and -33C/T (rs2070874) IL4 gene polymorphisms are implicated in paranoid schizophrenia development in the Polish population. Genotyping of polymorphisms was performed by using PCR-RFLP technique. The genotypes and alleles distribution of both SNPs were analysed in patients (n = 182) and healthy individuals constituted the control group (n = 215). The connection between some clinical variables and studied polymorphisms has been examined as well. We did not revealed any association between the -590C/T and -33C/T polymorphisms and paranoid schizophrenia. In case of both SNPs the homozygous TT genotype was extremely rare. Both polymorphic sites of the IL4 gene were found to be in a very strong linkage disequilibrium. However we did not identify a haplotype predispose to paranoid schizophrenia. No associations were also observed between the clinical course and psychopathology of the disease and the genotypes of both analysed polymorphisms. Our results suggest that the polymorphisms -590C/T in IL4 gene promoter region and -33C/T in the 5'-UTR are not involved in the pathophysiology of paranoid schizophrenia in Polish residents.     

Association between Single Nucleotide Polymorphisms in the ADD3 Gene and Susceptibility to Biliary Atresia

Background and Objectives

Based on the results of previous studies, the ADD3 gene, located in the 10q24.2 region, may be a susceptibility gene of biliary atresia (BA). In this study, two single nucleotide polymorphisms (SNPs) in the ADD3 gene, rs17095355 C/T and rs10509906 G/C, were selected to investigate whether there is an association between these SNPs and susceptibility to BA in a Chinese population.

Methods

A total of 752 Han Chinese (134 BA cases and 618 ethnically matched healthy controls) were included in the present study. The ADD3 gene polymorphisms were genotyped using a TaqMan genotyping assay.

Results

Positive associations were found for the SNP rs17095355 in the codominant model; specifically, the frequencies of the CT and TT genotypes and the T allele were higher in the cases than the controls, demonstrating a significant risk for BA (odds ratio [OR] = 1.62, 95% confidence interval [CI] = 1.02–2.58; OR = 2.89, 95% CI = 1.72–4.86; and OR = 1.75, 95% CI = 1.34–2.29, respectively). Regarding rs10509906, the per-C-allele conferred an OR of 0.70 (95% CI = 0.49–1.00) under the additive model. A greater risk of BA was associated with the T_a-G_b (a for rs17095355 and b for rs10509906) haplotype (OR = 1.82, 95% CI = 1.27–2.61) compared with the C_a-C_b haplotype.

Conclusion

This study suggests that the ADD3 gene plays an important role in BA pathogenesis and reveals a significant association between two SNPs, rs17095355 and rs10509906, and BA.     

Association of polymorphisms in the human IL4 and IL5 genes with atopic bronchial asthma and severity of the disease

Two polymorphisms in the IL4 (G/C 3'-UTR) and IL5 (C-703T) genes were studied in a sample of families whose probands had atopic bronchial asthma (BA) (66 families, n = 183) and in a group of non-cognate individuals with the severe form of the disease (n = 34). The samples were collected from the Russian population in the city of Tomsk (Russia). Using the transmission/disequilibrium test (TDT), a significant association of allele C-703 IL5 with BA was established (TDT = 4.923, p = 0.007 +/- 0.0007). The analysis of 40 individuals with mild asthma and 49 patients with the severe form of the disease revealed a negative association of genotype GG IL4 (OR = 0.39, 95% CI = 0.15-0.99, p = 0.035), and also a trend towards a positive association of the GC IL4 genotype (OR = 2.52, 95% CI = 0.98-6.57, p = 0.052) with mild BA. There was a concordance of the clinical classification of BA severity with the 'genotype' (McNemar's chi(2) test with continuity correction constituted 0.03, d.f. = 1, p = 0.859). These results suggest that polymorphisms in the IL4 and IL5 genes contribute to the susceptibility to atopic BA and could determine the clinical course of the disease.     

A novel polymorphism in the 5' promoter region of the human interleukin-4 receptor alpha-chain gene is associated with decreased soluble interleukin-4 receptor protein levels

Interleukin (IL)-4 exerts its biological effects through binding to the IL-4 receptor (IL4R) complex, plays a central role in stimulating B-cell differentiation, and is crucial for the development of T helper 2 cells. Recently, a soluble form of the human IL4R alpha chain (sIL4R alpha), which is produced by alternate mRNA splicing of exon 8, was discovered. sIL4R is thought to play an important role in either enhancing or inhibiting IL-4 signalling. We analyzed the 5' promoter region of the human IL4R alpha-chain gene (IL4RA) of healthy volunteers by DNA sequencing and found three novel single-nucleotide polymorphisms (SNPs; T-890C, T-1914C, C-3223T) and one novel short tandem repeat [(CAAAA)(5-7)-3600]. The two common promoter region SNPs T-1914C and C-3223T as well as six known coding SNPs in the IL4RA gene were genotyped in healthy blood donors by PCR with sequence-specific primers; total sIL4R levels were measured by ELISA. Results revealed a highly significant association of the -3223T variant with lowered sIL4R levels (two-tailed t-test, P=0.0002). Results remained highly significant after Bonferroni adjustment for multiple comparisons (P=0.0017). Moreover, the C-3223T variant was found to be in strong linkage disequilibrium with the extracellular 150V variant (P<0.001), which was recently described to be associated with atopic asthma in a Japanese population. Since this novel IL4RA promoter region SNP is common (allele frequency 29.8%), we conclude that it may be of importance for the genetic regulation of the IL-4 signalling pathway.     

Interleukin-4 -590T/C polymorphism influences the susceptibility to nonsmall cell lung cancer

Lung cancer is the leading cause of cancer mortality worldwide. Nonsmall cell lung cancer (NSCLC) accounts for most of these cases. Interleukin 4 (IL-4) is a typical pleiotropic T helper 2 cytokine and plays crucial roles in tumor immunology. IL-4 gene -590T/C polymorphism has been shown to be associated with different autoimmune diseases and cancers. The present study evaluated the correlation between this polymorphism and the susceptibility to NSCLC in the Chinese population. The IL-4 variant -590T/C was detected by polymerase chain reaction-restriction fragment length polymorphism in 1072 NSCLC cases and 1126 age-matched healthy controls. Data were analyzed using the Chi-square test. Results showed that frequencies of IL-4 -590 TC, CC genotype, and -590 C allele were significantly lower in patients with NSCLC than in healthy controls (odds ratio [OR]=0.77, 95% confidence interval [CI] 0.64-0.93, p=0.006; OR=0.54, 95% CI 0.38-0.76, p=0.0004; and OR=0.72, 95% CI 0.62-0.83, p=1.1 × 10(-5), respectively). Our data suggest that the -590T/C polymorphism of the IL-4 gene is associated with a decreased susceptibility to NSCLC.     

T cells specific for Candida albicans antigens and producing type 2 cytokines in lesional mucosa of untreated HIV-infected patients with pseudomembranous oropharyngeal candidiasis

Factors influencing the susceptibility to mucosal candidiasis in HIV-infected patients are not clearly understood. Since in animal models of candidiasis the T helper (Th)1- or Th2-responses are protective or non-protective, respectively, this study was aimed to evaluate the cytokine profile of T-cell response to Candida albicans in the blood and lesional tissues of human immunodeficiency virus (HIV)-infected individuals, suffering, or not, from pseudomembranous oropharyngeal candidiasis (POPC), of HIV-negative women suffering from recurrent vaginal candidiasis (RVC) and of healthy controls. Peripheral blood mononuclear cells from HIV-infected and RVC patients proliferated to C. albicans antigen more than controls. Upon antigen activation, T cells from HIV-infected patients produced low interferon (IFN)-gamma, while only T cells from patients with POPC displayed high interleukin (IL)-4 and IL-5 production. POPC-positive patients also showed higher serum IgE levels than POPC-negative patients. T-cell clones generated from the oral mucosa of one HIV-infected patient with POPC produced IL-4, but not IFN-gamma (Th2 phenotype), whereas clones obtained from vaginal mucosa from one RVC patient or one healthy donor showed a Th1 profile. These findings, showing a non-protective Th0/Th2 response to C. albicans antigen in the blood and lesional mucosa of HIV-infected patients with POPC, may explain the high susceptibility of candidiasis in these subjects.     

Genetic variation in IL28B is associated with the development of hepatitis B-related hepatocellular carcinoma

To evaluate the role of host IL28B (interleukin 28B; interferon lambda 3) single nucleotide polymorphisms (SNPs) in predicting hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) susceptibility, three SNPs in the IL28B gene (rs12979860C/T, rs8099917G/T and rs12980275G/A) were examined in 330 subjects (including 154 HBV-related HCC patients, 86 non-HCC patients with chronic hepatitis B (CHB), 43 HBV self-limited infections and 47 healthy controls). Notably, the frequency of CC homozygosity was 91.5% in healthy controls and 72.9% in CHB, the difference being statistically significant (χ(2) = 6.40, P = 0.01). The statistically difference was seen between healthy controls (91.5%) and HCC (74.7%) (χ(2) = 6.05, P = 0.01). However, this significant finding was not seen between HBV self-limited and healthy controls. Carriers of the minor T allele in rs12979860 had a higher risk of HCC compared with non-carriers (χ(2) = 4.44, P = 0.04). Haplotype analyses revealed significant association between haplotype C-T-A and healthy controls, but not with the HCC group (96.6 vs. 82.0%, χ(2) = 6.08, P = 0.01). Analyses of genotype combination and gene-gene interaction showed that there was a positive interaction between rs12979860 and rs12980275, with an OR rate of 11.79 (likelihood test, P = 0.04). Our results suggest that the IL28B rs12979860 C/T polymorphism might affect susceptibility to the chronic HBV infection and progression of HCC. Of note, the T allele and non-CC genotypes have strong predictive effect of increasing susceptibility of chronic HBV infection and HCC.     

Polymorphism of interleukins and interleukin receptor genes: population distribution and association with atopic bronchial asthma

Population distribution and pathogenetic significance for bronchial asthma (BA) of the eight polymorphic variants of six interleukin--(IL) and interleukin receptor genes, C-589T, G/C 3'-UTR IL4, C-703T IL5, T113M IL9, Q551R, 150V IL4RA, and G1972A IL5RB, was examined. In the population samples of Russians, Tajiks, Buryats, and Tuvinians racial and ethnic specificity of these polymorphisms was established. These specific features were manifested as population-specific "enetic portraits" in respect of polymorphic allele frequencies. Analysis of the BA patients and their relatives from Tomsk by use of transmission/disequilibrium test (TDT) revealed the presence of a statistically significant association between the C-703 IL5 allele and the disease (P = 0.005). This is the first evidence of an association between the IL5 gene polymorphism and BA.     

Association of the solute carrier family 11 member 1 gene polymorphisms with susceptibility to leprosy in a Brazilian sample

Natural resistance-associated macrophage protein 1/solute carrier family 11 member 1 gene (Nramp1/Slc11a1) is a gene that controls the susceptibility of inbred mice to intracellular pathogens. Polymorphisms in the human Slc11a1/Nramp1 gene have been associated with host susceptibility to leprosy. This study has evaluated nine polymorphisms of the Slc11a1/Nramp1 gene [(GT)n, 274C/T, 469+14G/C, 577-18G/A, 823C/T, 1029 C/T, 1465-85G/A, 1703G/A, and 1729+55del4] in 86 leprosy patients (67 and 19 patients had the multibacillary and the paucibacillary clinical forms of the disease, respectively), and 239 healthy controls matched by age, gender, and ethnicity. The frequency of allele 2 of the (GT)n polymorphism was higher in leprosy patients [p = 0.04, odds ratio (OR) = 1.49], whereas the frequency of allele 3 was higher in the control group (p = 0.03; OR = 0.66). Patients carrying the 274T allele (p = 0.04; OR = 1.49) and TT homozygosis (p = 0.02; OR = 2.46), such as the 469+14C allele (p = 0.03; OR = 1.53) of the 274C/T and 469+14G/C polymorphisms, respectively, were more frequent in the leprosy group. The leprosy and control groups had similar frequency of the 577-18G/A, 823C/T, 1029C/T, 1465-85G/A, 1703G/A, and 1729+55del4 polymorphisms. The 274C/T polymorphism in exon 3 and the 469+14G/C polymorphism in intron 4 were associated with susceptibility to leprosy, while the allele 2 and 3 of the (GT)n polymorphism in the promoter region were associated with susceptibility and protection to leprosy, respectively.     

Polymorphism analysis of the CTLA-4 gene in paracoccidioidomycosis patients

The CTLA-4 protein is expressed in activated T cells and plays an essential role in the immune response through its regulatory effect on T cell activation. Polymorphisms of the CTLA-4 gene have been correlated with autoimmune, neoplastic and infectious illnesses. This work aimed to verify possible associations between single nucleotide polymorphisms (SNPs) in CTLA-4, -318C/T in the promoter and +49A/G in exon 1 and paracoccidioidomycosis (PCM) caused by Paracoccidioides brasiliensis. For this purpose, 66 chronic form PCM patients and 76 healthy controls had their allele, genotype and haplotype frequencies determined. The genetic admixture structure of the patients and controls was evaluated to eliminate ancestral bias. The comparison of frequencies indicated no significant differences between patients and controls that could link the SNPs to PCM. Groups were admixture matched with no difference observed in population ancestry inference, indicating that the absence of association between CTLA-4 polymorphisms and PCM could not be attributed to ancestral bias. This study showed that there was no association between the CTLA-4 SNPs -318 and +49 and the resistance or susceptibility to PCM.     

Influence of interleukin-12 receptor β1 polymorphisms on tuberculosis

Host genetic factors may be important determinants of susceptibility to tuberculosis, and several candidate gene polymorphisms have been shown to date. A series of recent reports concerning rare human deficiencies in the type-1 cytokine pathway suggest that more subtle variants of relevant genes may also contribute to susceptibility to tuberculosis at the general population level. To investigate whether polymorphisms in the interleukin-12 receptor (IL-12R) gene predispose individuals to tuberculosis, we studied these genes by single-strand conformational polymorphism analysis and direct sequencing. Although no common polymorphisms could be identified in the IL-12R beta 2 gene ( IL-12RB2), we confirmed four single nucleotide polymorphisms (SNPs; 641A-->G, 684C-->T, 1094T-->C, and 1132G-->C) causing three missense variants (Q214R, M365T, G378R) and one synonymous substitution in the extracellular domain of the IL-12R beta 1 gene ( IL12RB1). All SNPs were in almost perfect linkage disequilibrium (D'=0.98), and two common haplotypes of IL12RB1(allele 1: Q214-M365-G378; allele 2: R214-T365-R378) were revealed. Polymerase chain reaction/restriction fragment length polymorphism and sequence analyses were used to type IL12RB1polymorphisms in 98 patients with tuberculosis and 197 healthy controls in Japanese populations. In our case-control association study of tuberculosis, the R214-T365-R378 allele (allele 2) was over-represented in patients with tuberculosis, and homozygosity for R214-T365-R378 (the 2/2 genotype) was significantly associated with tuberculosis (odds ratio: 2.45; 95% CI: 1.20-4.99; P=0.013). In healthy subjects, homozygotes for R214-T365-R378 had lower levels of IL-12-induced signaling, according to differences in cellular responses to IL-12 between two haplotypes. These data suggest that the R214-T365-R378 allele, i.e., variation in IL12RB1, contribute to tuberculosis susceptibility in the Japanese population. This genetic variation may predispose individuals to tuberculosis infection by diminishing receptor responsiveness to IL-12 and to IL-23, leading to partial dysfunction of interferon-gamma-mediated immunity.     

Polymorphisms of the candidate genes for genetic susceptibility to tuberculosis in the Slavic population of Siberia: a pilot study

The 469 + 14 G/C (INT4), 1465 - 85 G/A, and C274T polymorphisms of NRAMP1 and the A/C polymorphism of IL12 3'-UTR were analyzed in ethnic Russians with (N = 58) or without (N = 127) tuberculosis (TB) from Tomsk. On evidence of allele and genotype frequencies, none of the polymorphisms was associated with TB. In the healthy controls, the three NRAMP1 polymorphisms were in linkage disequilibrium with each other (P < 0.001) but not with the IL12 polymorphism. Still the four polymorphisms are potentially informative as concerns their association with TB.     

Genetic variants of IL6 gene promoter influence on C-reactive protein levels but are not associated with susceptibility to invasive pulmonary aspergillosis in haematological patients

Several lines of evidence indicate that IL6 plays a major role in the pathogenesis of a number of infectious diseases. The purpose of this study was to determine whether IL6 promoter polymorphisms were genetic markers of susceptibility to invasive pulmonary aspergillosis (IPA). To clarify the relationship between IL6 variants and IPA susceptibility, the IL6−174(G/C) and IL6−634(G/C) promoter single nucleotide polymorphisms (SNPs) were defined and plasma concentrations of IL6 and C-reactive protein (CRP) were measured. The study included 130 patients with haematological malignancies and 145 unrelated healthy individuals. No significant genotypic and allelic differences were found between patients and healthy controls. IPA was diagnosed in 71 of 130 patients according to the consensus criteria. CRP values were significantly associated with both IL6−174(G/C) and IL6−634(G/C) polymorphisms. However, IL6 and CRP values were similar between IPA and non-IPA groups. Neither IL6−174(G/C) nor IL6−634(G/C) polymorphisms were associated with IPA infection (p = 0.414 and p = 0.184, respectively). No evidence of association was found between allelic frequencies of IL6 promoter polymorphisms and IPA infection (p = 0.864 and p = 0.104, respectively). Further, no association was detected between IL6 genotypes and clinical profiles in IPA patients. Haplotype analysis also revealed that IL6 gene was not associated with IPA susceptibility in a Spanish population (Global haplotype association p value: 0.31). These findings suggest that IL6 polymorphisms influence on CRP circulating levels but are not associated with IPA susceptibility. Because the sample size is relatively small in our series, larger investigations of IL6−174(G/C)/IL6−634(G/C) genotypes and haplotypes are needed to clarify the potential role of this gene in the pathophysiology of IPA infection.     

Single Nucleotide Polymorphisms in IL8 and TLR4 Genes as Candidates for Digital Dermatitis Resistance/Susceptibility in Holstein Cattle

Relatedness between single nucleotide polymorphisms in IL8 and TLR4 genes and digital dermatitis resistance/susceptibility was investigated in seventy Holstein dairy cows. Animals were assigned into two groups, affected group (n?=?35) and resistant group (n?=?35) based on clinical signs and previous history of farm clinical records. Blood samples were collected for DNA extraction to ampliy fragments of 267-bp and 382-bp for IL8 and TLR4 genes, respectively. PCR-DNA sequencing revealed three SNPs in each of IL8 and TLR4 genes. The identified SNPs associated with digital dermatitis resistance were C94T, A220G, and T262A for IL8 and C118T for TLR4. However, the G349C and C355A SNPs in TLR4 gene were associated with digital dermatitis susceptibility. Chi-square analysis for comparison the distribution of all identified SNPs in both IL8 and TLR4 genes between resistant and affected animals showed no significant variation among the identified SNPs in IL8 gene. Meanwhile, there was a significant variation in case of TLR4 gene. As a pilot study, the present results revealed that identified SNPs in IL8 and TLR4 genes can be used as a genetic marker and predisposing factor for resistance/susceptibility to digital dermatitis in dairy cows. However, TLR4 gene may be a potential candidate for such disease.     

Multi-drug resistance-1 gene polymorphisms in nephrotic syndrome: Impact on susceptibility and response to steroids

Background

Role of multidrug resistance-1 (MDR-1) gene polymorphisms has not been clarified in nephrotic syndrome (NS). Additionally, researchers studied several genetic polymorphisms to explain their influence on different patients' responses to steroid; however the data were inconsistent. Therefore, we aimed to investigate the association of MDR-1 gene polymorphisms [C1236T, G2677T/A, C3435T] and haplotypes with susceptibility to childhood nephrotic syndrome, and whether they influence steroid response.

Methods

We detected MDR-1 gene polymorphisms using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) in 138 NS patients and 140 age and sex matched healthy children.

Results

The frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele, MDR1 C3435T TT genotype, and T allele genotype frequencies were significantly increased in NS group. While no significant differences were observed in distributions of C1236T genotypes or allele between NS patients and healthy children. Moreover, steroid non-responder NS patients had significantly higher frequencies of MDR1 G2677T/A GT, GA, and TT + AA genotypes than steroid responsive NS patients. We observed also that NS patients with age less than 6 years old had increased frequencies of MDR1 G2677T/A GT, GA, TT + AA genotypes or T allele MDR1 C3435T CT, TT genotypes and T allele. Interestingly the frequency of the TGC haplotype of MDR1 was lower in the initial steroid responders than in non-responders NS patients. On the contrary, there were no any association between the MDR1 haplotypes with NS susceptibility and they did not influence renal pathological findings.

Conclusion

Our data suggested that MDR1 C3435T or G2677T/A gene polymorphisms are risk factors of increased susceptibility, earlier onset of NS, and steroid resistance.