Tag: haplotypes

Killer Cell Immunoglobulin-like Receptor Genotype and Haplotype Investigation of Natural Killer Cells from an Australian Population of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis Patients

Abstract:

Killer cell immunoglobulin-like receptor (KIR) genes encode for activating and inhibitory surface receptors, which are correlated with the regulation of Natural Killer (NK) cell cytotoxic activity. Reduced NK cell cytotoxic activity has been consistently reported in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) patients, and KIR haplotypes and allelic polymorphism remain to be investigated.

The aim of this article was to conduct a pilot study to examine KIR genotypes, haplotypes, and allelic polymorphism in CFS/ME patients and nonfatigued controls (NFCs). Comparison of KIR and allelic polymorphism frequencies revealed no significant differences between 20 CFS/ME patients and 20 NFCs.

A lower frequency of the telomeric A/B motif (P < 0.05) was observed in CFS/ME patients compared with NFCs. This pilot study is the first to report the differences in the frequency of KIR on the telomeric A/B motif in CFS/ME patients. Further studies with a larger CFS/ME cohort are required to validate these results.

 

Source: Huth TK, Brenu EW, Staines DR, Marshall-Gradisnik SM. Killer Cell Immunoglobulin-like Receptor Genotype and Haplotype Investigation of Natural Killer Cells from an Australian Population of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis Patients. Gene Regul Syst Bio. 2016 Jun 19;10:43-9. doi: 10.4137/GRSB.S39861. ECollection 2016. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4913894/ (Full article)

 

Mitochondrial DNA variants correlate with symptoms in myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

BACKGROUND: Mitochondrial dysfunction has been hypothesized to occur in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), a disease characterized by fatigue, cognitive difficulties, pain, malaise, and exercise intolerance. We investigated whether haplogroup, single nucleotide polymorphisms (SNPs), or heteroplasmy of mitochondrial DNA (mtDNA) were associated with health status and/or symptoms.

METHODS: Illumina sequencing of PCR-amplified mtDNA was performed to analyze sequence and extent of heteroplasmy of mtDNAs of 193 cases and 196 age- and gender-matched controls from DNA samples collected by the Chronic Fatigue Initiative. Association testing was carried out to examine possible correlations of mitochondrial sequences with case/control status and symptom constellation and severity as reported by subjects on Short Form-36 and DePaul Symptom Questionnaires.

RESULTS: No ME/CFS subject exhibited known disease-causing mtDNA mutations. Extent of heteroplasmy was low in all subjects. Although no association between mtDNA SNPs and ME/CFS vs. healthy status was observed, haplogroups J, U and H as well as eight SNPs in ME/CFS cases were significantly associated with individual symptoms, symptom clusters, or symptom severity.

CONCLUSIONS: Analysis of mitochondrial genomes in ME/CFS cases indicates that individuals of a certain haplogroup or carrying specific SNPs are more likely to exhibit certain neurological, inflammatory, and/or gastrointestinal symptoms. No increase in susceptibility to ME/CFS of individuals carrying particular mitochondrial genomes or SNPs was observed.

 

Source: Billing-Ross P, Germain A, Ye K, Keinan A, Gu Z, Hanson MR. Mitochondrial DNA variants correlate with symptoms in myalgic encephalomyelitis/chronic fatigue syndrome. J Transl Med. 2016 Jan 20;14:19. doi: 10.1186/s12967-016-0771-6. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4719218/ (Full article)

 

Molecular study of receptor for advanced glycation endproduct gene promoter and identification of specific HLA haplotypes possibly involved in chronic fatigue syndrome

Abstract:

The receptor for advanced glycation end product (RAGE) is thought to play an important role in inflammation. Chronic fatigue syndrome (CFS) is a long-lasting fatigue that compromises at least 50% of a subject’s daily activities without other known cause. Immune dysfunction has been implicated and an association with a peculiar genetic cytokine profile, predisposing to an immunomodulatory response of inflammatory nature, was found.

The aim of this study is to analyse RAGE polymorphisms and HLA-DRB1 alleles in seventy-five Italian CFS patients and 141 controls matched for age, sex and ethnicity. These two groups underwent genomic study for RAGE 374T/A and 429C/T promoter polymorphisms; moreover, 46 patients and 186 controls were typed for HLA-DRB1 at low resolution molecular level. Of these, 31 patients and 99 controls also underwent high resolution analysis to define the HLA-DRB1*11 and DRB1*13 alleles.

The haplotypes RAGE-374T, DRB1*04; RAGE-374T, DRB1*09; RAGE-374T, DRB1*11; RAGE-374A, DRB1*13; RAGE-429T, DRB1*04 and RAGE-429C, DRB1*11 were significantly more frequent in CFS patients, whereas RAGE-429C, DRB1*07 would seem protective. A significantly lower frequency of DRB1*1104 (5.4% vs 12.9% p=0.04, OR=0.39) and a significantly higher frequency of HLA-DRB1*1301 (13.0% vs 5.1% p=0.006, OR= 2.79) were found in CFS patients. A synergic effect was observed with RAGE polymorphism.

The OR values strengthened in the following cis combinations: RAGE-374A, HLA-DRB1*1104 (OR=0.27) and RAGE-374A, HLADRB1*1301 (OR=6.23). HLA haplotypes rather than single alleles of RAGE or of DRB1 genes seem to be involved in CFS, probably including a subregion of major interest.

 

Source: Carlo-Stella N, Bozzini S, De Silvestri A, Sbarsi I, Pizzochero C, Lorusso L, Martinetti M, Cuccia M. Molecular study of receptor for advanced glycation endproduct gene promoter and identification of specific HLA haplotypes possibly involved in chronic fatigue syndrome. Int J Immunopathol Pharmacol. 2009 Jul-Sep;22(3):745-54. https://www.ncbi.nlm.nih.gov/pubmed/19822091