Association study of copy number variants in CCL3L1, FCGR3A and FCGR3B genes with risk of ankylosing spondylitis in a West Algerian population.

Numerous single nucleotide polymorphisms (SNPs) were explored in the Algerian population to evaluate associated ankylosing spondylitis (AS) genetic risk factors, but no study has identified the impact of copy number variations (CNVs). The aim of the study was to determine whether CNVs of CCL3L1, FCGR3A and FCGR3B genes were also associated with the susceptibility of AS disease in Algerian population. The data set of the current study is composed of 81 patients with AS and 119 healthy controls. All samples were genotyped by digital droplet PCR (ddPCR). Chi-square test and OR calculation were used to evaluate association between CNVs and AS and the risk associated with copy numbers (CN). In results, FCGR3A CN less than two copies (<2) was significantly increased in spondylitis patients (p = .0001, OR = 7.74 [2.32-25.74]). Additionally, FCGR3A CN < 2 copies association was present only in HLA-B27 (-) patients. We have concluded that FCGR3A deletions have an independent effect on AS regarding HLA-B27 status. This is the first study that investigated the CCL3L1 CNVs in relation to AS risk disease. It reveals that CCL3L1 and FCGR3B CNVs may not be involved in susceptibility to AS risk in the Algerian population.

Metabolic Imbalance and Vitamin D Deficiency in Type 1 Diabetes in the Algerian Population.

BACKGROUND: We aimed to assess Vitamin D levels in patients with Type 1 Diabetes (T1D) and to investigate the correlation between vitamin D and metabolic imbalance. MATERIAL AND METHODS: For our study, we selected thirty-one patients with T1D without complications and fifty-seven healthy controls. Diabetic patients were diagnosed using the criteria of the World Health Organization/American Diabetes Association. Vitamin D, Parathyroid Hormone (PTH), insulin and C peptide assay were performed using chimilunescence. Glucose level, lipid profile, glycated haemoglobin (HbA1c) and ionogram were also analysed. RESULTS: Vitamin D, HbA1c and Gly levels were found to be significant in T1D patients than in controls (P<0.5). However, for PTH, no significant difference was observed (P > 0. 05) and the results show a non-significant difference of total cholesterol potassium, sodium, phosphor and calcium concentration averages. CONCLUSION: Our results indicate that the deficiency of VD is associated with an increased risk of T1DM in Algerian population.

Human Leukocyte Antigens (HLA) Genes Association in Type 1 Diabetic Nephropathy.

BACKGROUND: Diabetic nephropathy is a common worldwide multifactorial disease where involvement of genetic factors is well etablished. The aim of this study was to investigate the HLA genes implication in the development of type 1 diabetic nephropathy. METHODS: We performed a case- control study where one hundred and fifty subjects were examined. Patients were divided in two groups; with and without type 1 diabetic nephropathy. HLA typing was performed using Polymerase Chain Reaction- Sequence Specific Oligonucleotide (PCR- SSO) method. HLA association to clinical phenotype and HLA haplotype analysis was also investigated. RESULTS: HLA B*51 is increased in patients without type 1 diabetic nephropathy (7.14% vs. 0 %, P <0.05, OR= 0), however no other studied alleles seem to have any effect (all P>0.05). Haplotype analysis also does not reveal any significant association, however, A*02-B*18-DRB1*03-DQA1*05- DQB1*03 haplotype shows a tendency to be associated with the development of diabetic nephropathy (P = 0.05). CONCLUSION: These results suggest a protective effect of HLA B*51 allele from type 1 diabetic nephropathy. However, further studies are required in order to clarify its potential implication as a protective marker.

Functional polymorphisms of Monocyte Chemoattractant Protein-1 gene and Pott's disease risk.

OBJECTIVE: Monocyte Chemoattractant Protein-1 (MCP-1/CCL2), a key player in immune-mediated responses against Mycobacterium tuberculosis, is encoded by a polymorphic gene. Functionally relevant polymorphic variations in the MCP-1 gene have been associated with both susceptibility to and protection against tuberculosis-related disorders. Here, we investigated the potential impact of some of these polymorphisms on Pott's disease risk in a patient cohort from Algeria. METHODS: DNA from 132 Algerian patients with exclusive Pott's disease and 204 healthy controls, included under a case-control design, were analyzed for the MCP1 -2518A/G (rs1024611), -362G/C (rs2857656) and int1del554-567 (rs3917887) polymorphisms. PHASE software was used for haplotype reconstruction. Genetic associations were examined using chi-square tests. RESULTS: We found that the rs1024611 -2518 GG, rs2857656 -362 CC and rs3917887 int1del554-567 del/del homozygous genotypes each were significantly more prevalent in patients than in controls (respective corrected p value [Pc]=0.01, 0.04 and 0.04) Haplotype distribution profile further confirmed this, as the homozygous combination of GCdel haplotype was also found with raised susceptibility to Pott's disease (Pc=0.03). CONCLUSION: Our findings confirm and replicate the recent data from China (which dealt essentially with rs1024611 and rs2857656) and also reinforce them by providing trans-ethnic evidence and extending the genetic association to the rs3917887.

HLA Polymorphism in Algerian Children With Lymphomas.

BACKGROUND: Non-Hodgkin lymphoma (NHL) and Hodgkin lymphoma (HL) are the 2 types of lymphoma that represent the third most common childhood malignancy. Multiple etiological factors are involved in lymphoma pathogenesis, including viral infection, immune deficiencies, environmental agents, and genetic factors. Strong arguments supporting a genetic linkage between the susceptibility to lymphomas and human leukocyte antigens (HLA) are reported and give an idea about susceptibility or protection from the disease. METHODS: Seventy-one cases were included in this study: 36 cases of non-Hodgkin lymphoma and 35 patients with Hodgkin lymphoma. Their ages ranged from 4 to 18 years. The control group consisted of 70 unrelated healthy individuals, with a mean age of 5 to 17 years. The genotype of HLA-A, HLA-B, HLA-DR, and HLA-DQ alleles was typed by means of PCR sequence-specific priming. RESULTS: HLA-B*18, HLA-DRB1*03, *07, and HLA-DQB1*02 were significantly increased in patients with lymphomas when compared with controls, whereas HLA-DRB1*13 and DQB1*03 were significantly decreased when compared with controls. CONCLUSIONS: These results indicate that HLA-B*18, DRB1*03, *07, and DQB1*02 may contribute to lymphoma susceptibility, whereas HLA-DRB1*13 and DQB1*03 may confer protection to lymphoma in the Algerian population.

Association of major histocompatibility complex class 1 chain-related gene a dimorphism with type 1 diabetes and latent autoimmune diabetes in adults in the Algerian population.

Major histocompatibility complex class I chain-related gene A (MICA-129) dimorphism was investigated in 73 autoimmune diabetes patients (type 1 diabetes and latent autoimmune diabetes in adults) and 75 controls from Algeria. Only MICA-129 Val allele and MICA-129 Val/Val genotype frequencies were higher among patients than in the control group. Statistical analysis of the estimated extended HLA-DR-DQ-MICA haplotypes shown that individual effects of MICA alleles on HLA-DQ2-DR3-MICA-129 Val/Val and HLA-DQ8-DR4-MICA-129 Val/Val haplotypes were significantly higher in patients than in the control groups. These preliminary data might suggest a relevant role of MICA-129 Val/Val single nucleotide polymorphism (weak/weak binders of NKG2D receptor) in the pathogenesis of T1D and LADA.

MICA-129 genotype, soluble MICA, and anti-MICA antibodies as biomarkers of chronic graft-versus-host disease.

The MHC class I-related chain A (MICA) molecules exist as membrane-bound and soluble isoforms and are encoded by a polymorphic gene. Their genetic and phenotype characteristics have been studied in various pathologic settings but not in the context of hematopoietic stem cell transplantation (HSCT). Here, we evaluated whether MICA-related features namely MICA-129 gene polymorphism, serum levels of soluble MICA (sMICA) and anti-MICA antibodies (MICA Abs) before and after HSCT could influence the incidence of chronic graft-versus-host disease (cGVHD) and relapse of their disease in 211 HLA-identical sibling pairs and in a subset of 116 recipients, respectively. Although the MICA-129 val/val genotype and elevated sMICA serum levels after HSCT are independently associated with the incidence of cGVHD (P = .002 and .001) regardless of history of acute GVHD, the presence of MICA Abs before transplantation confers protection against cGVHD (P = .04). There is an inverse relationship between MICA Abs and sMICA, suggesting an antibody-based neutralization of deleterious effects of sMICA. Similarly, these genetic and phenotype characteristics of MICA influence the incidence of relapse. Altogether, these data suggest that the studied MICA genotype and phenotype specificities could be used as relevant biomarkers for cGVHD monitoring.

Early-onset ankylosing spondylitis is associated with a functional MICA polymorphism.

Major histocompatibility complex (MHC) class I chain-related A (MICA) molecules deliver activating signals through the NKG2D receptor expressed on the surface of natural killer (NK), CD8alphabeta and gammadelta T cells, and the MICA gene is polymorphic. The recently described MICA amino acid substitution at position 129 (MICA-129) seems to affect its binding to NKG2D. We investigated whether this dimorphism (MICA-129met [methionine] and MICA-129val [valine]) is associated with susceptibility to ankylosing spondylitis (AS) in a cohort of Algerian patients stratified according to their HLAB27 status and the age of onset of the disease. DNA from 129 patients and 76 healthy individuals were analyzed to determine the HLA-B generic type as well as MICA-129 polymorphism. Statistical analysis revealed: (1) a weaker association between AS and HLA-B27 in Algerians than in that reported for European patients (63% versus 80-90%), suggesting a possible influence of other genetic/environmental determinants in the studied population and (2) an association between MICA-129 met/met genotype and juvenile AS (p = 0.02) independent of HLA-B27 status. These data suggest a potential role for a functionally relevant MICA gene polymorphism in autoimmune/inflammatory disease susceptibility.