Mutant Allele Research Articles

Diagnosis of lactose intolerance: concordance between 13910-C/T genotype and lactose tolerance test in a Danish population

The association between the MCM6-13910-C/T polymorphism and lactose intolerance in individuals of European descent is well known. However, the notion that having a single versus a double allelic mutation might influence one’s phenotype has been hypothesized. This study investigated whether patients with the three genotypes C/C, C/T, T/T differed in response to a lactose tolerance test (LTT) in a Danish setting. Anonymized data on 603 individuals with results for both genetic test and LTT were investigated. Mean delta glucose values were plotted for the time points of the LTT (0, 15, 30, 45 and 60 min) for the C/C, C/T and T/T genotype, respectively. Further, the agreement between the three genotypes and the diagnostic interpretation of the LTT were examined using a cut-off of > 1.4 mmol/L rise in glucose. In subjects with the C/C genotype, mean glucose delta levels were markedly lower compared to both the C/T and T/T genotypes at all time points. Overall, a difference between mean glucose delta values among the C/T and T/T genotype could not be shown. Using a LTT cut-off of > 1.4 mmol/L, the proportions of lactose intolerant LTT results for each genotype were as follows: 58% among C/C, 5% among C/T, and 7% among T/T. In a Danish healthcare setting, the C/C genotype was on average associated with a smaller glucose response during a LTT when compared to the C/T and T/T genotypes. A marked difference in the LTT response among the C/T and T/T genotype was not observed.

The association of serum level and polymorphisms of IFN-γ (rs2069705) with the susceptibility to cutaneous leishmaniasis

Leishmaniasis, a broad range of parasitic diseases, caused by Leishmania which is a flagellated intracellular protozoan parasite of the family Trypanosomatidae. The severity of leishmaniasis diseases ranges from minor cutaneous lesions to severe visceral illnesses that can be disfiguring and life-threatening. Cytokines are glycoprotein molecules produced by various cells in response to various immunological triggers. They regulate the body’s innate and adaptive immunological responses. The aim of this study was to clarify the association of serum level and polymorphisms of IFN-γ with susceptibility to cutaneous leishmaniasis (CL). The whole blood 200 samples were collected from patients and controls from Diyala Governorate/ Iraq from October 2022 to February 2023 which were used to measure IFN-γ polymorphisms using High Resolution Melting technique. Enzyme-linked immunosorbent assay was used to detect the serum level of IFN-γ. The findings of this investigation showed that the IFN-γ serum concentration elevated significantly in patients compared to controls (P < 0.01). Also, the study found that the highest mean level IFN-γ concentrations were found in adults aged 46–55 years old for patients compared with controls with significant differences (P < 0.01). While, no significant differences were observed in the rest age groups except children aged 5–15 years old. Additionally, significant differences between patients and controls were revealed by polymorphisms data in all genetic models for genotypes GA, AA, (GA + AA) and allele A with (P < 0.01) and OR > 1. However, the distribution of IFN-γ serum levels by SNP (rs2069705) demonstrated no differences between genotypes except GG genotype which has significant differences for patients comparing to the same genotype in controls. Taking together, the SNP for IFN-γ (rs2069705) could be a risk factor for susceptibility infection with CL. Also, considered the mutant allele A as a risk allele and genotype AA in codominant genetic model as more risk factor than the genotype GA.

Novel Frameshift Variant of the MYBPC3 Gene Associated with Hypertrophic Cardiomyopathy Significantly Decreases the Level of This Gene’s Transcript in the Myocardium

Hypertrophic cardiomyopathy (HCM) is the most common inherited heart disease with a prevalence of 1 : 200–1 : 500 in the general population. The majority of HCM-linked pathogenic (or likely pathogenic) variants is located in eight genes encoding proteins of sarcomere, the main contractile unit of cardiomyocytes; one of these genes, MYBPC3, is the most commonly affected and usually associated with the more benign clinical course of the disease compared to other HCM-related genes. Here, we describe a novel frame shift variant NM_000256.3:c.2781_2782insCACA of the MYBPC3 gene that causes familial HCM in the heterozygous state. The proband had a progressive heart failure despite the surgical removal of left ventricular tract obstruction. Evaluation of levels of transcripts produced from the mutant allele and wild-type allele of the MYBPC3 gene in proband myocardial tissue and comparison of their total levels with ones in the control samples from patients without HCM showed a significant allele-specific reduction of mutant transcript levels. Our results expand the spectrum of known genetic variants with a proven role in the development of HCM.

Role of gene polymorphism in the development of disorders of the lipid profile in individuals exposed to chemicals

Introduction. The prevalence of arterial hypertension and dyslipidemia in the Russian population exceeds 50%. By a number of working industrial factors have been proved to play the negative role in their development. The results of earlier studies indicate to the epigenetic role of toxic substances in relation to various genes. The aim of the study was to establish associations of polymorphic variants of cardiovascular risk genes with disorders of lipid metabolism in workers performing liquidation works in the accumulated environmental risks zone. Materials and methods. Ninety two and 82 employees from Federal Environmental Operator (FEO) and EMERCOM, respectively were studied. Parameters of lipid metabolism and polymorphic variants of APOE Cys130Arg (rs429358) and PPARG Pro12Ala (rs1801282) genes were investigated. Results. In FEO workers, each variant allele of the APOE Cys130Arg gene is associated with impaired LDL-C concentration in an additive manner (OR = 2.69; 95% CI = 1.03–7.08, p=0.04). Carrying either the T/C or C/C variant allele of this polymorphic variant or the C/G or G/G polymorphic variant Pro12Ala of the PPARG gene increases the odds of developing abnormalities in total cholesterol levels by more than 3.5-times. The risk influence of the mutant genotype G/G and allele G on the increase of Apo B concentration was also established. In EMERCOM workers, the presence of both alleles of this polymorphic variant increased the probability of a decrease in HDL-H levels by 5 times. Limitations. Male persons are employees of the FEO and the Ministry of Emergency Situations. Age accounts of 30–50 years. Conclusions. An increased risk of deviations of total cholesterol concentration, proatherogenic cholesterol, and lipoprotein fractions associated with the PPARG Pro12Ala and APOE Cys130Arg genes polymorphisms was found in FEO workers, whereas only the reduced high-density lipoprotein cholesterol risk in carriers of the PPARG Pro12Ala gene mutant allele was found in EMERCOM workers.

The white gene as a transgenesis marker for the cricket Gryllus bimaculatus.

The cricket Gryllus bimaculatus is an emerging model insect of the order Orthoptera that is used in a wide variety of biological research themes. This hemimetabolous species appears highly complementary to Drosophila and other well-established holometabolous models. To improve transgenesis applications in G. bimaculatus, we have designed a transformation marker gene inspired from the widespread Drosophila mini-white+. Using CRISPR/Cas9, we first generated a loss-of-function mutant allele of the Gb-white gene (Gb-w), which exhibits a white eye coloration at all developmental stages. We then demonstrate that transgenic insertions of a piggyBac vector containing a 3xP3-Gb-w+ cassette rescue eye pigmentation. As an application, we used this vector to generate G. bimaculatus lines expressing a centromeric histone H3 variant (CenH3.1) fused to EGFP and validated EGFP-CenH3.1 detection at cricket centromeres. Finally, we demonstrate that Minos-based germline transformation and site-specific plasmid insertion with the ΦC31 integrase system function in G. bimaculatus.

Disappearance of Cdc14 from the daughter spindle pole body requires Glc7-Bud14.

The conserved phosphatase Cdc14 facilitates mitotic exit in budding yeast by counteracting mitotic cyclin-dependent kinase activity. Cdc14 is kept in the nucleolus until anaphase onset, when it is released transiently into the nucleoplasm. In late anaphase, Cdc14 is fully released into the cytoplasm upon activation of the mitotic exit network (MEN) to trigger mitotic exit. Cdc14 also localizes to yeast spindle pole bodies (SPBs) in anaphase and dephosphorylates key targets residing on SPBs to allow SPB duplication and prime the MEN. Protein phosphatase 1 (Glc7) with regulatory subunit Bud14 is another phosphatase that plays a key role in the spatiotemporal control of mitotic exit. In this study, we investigated the regulation of Cdc14 localization by Bud14-Glc7. We used fluorescence microscopy to analyze Cdc14 localization in BUD14 wildtype and BUD14 knockout cells (bud14Δ) as well as in cells expressing a mutant allele of BUD14 (bud14-F379A) that cannot bind Glc7. We also utilized a yeast two-hybrid (Y2H) system to examine the interaction of Bud14 with Cdc14. We found that Cdc14 remains at the SPBs longer in bud14Δ and bud14-F379A compared to wildtype cells. This effect is limited to the SPB that has migrated to the daughter cell (dSPB). Cdc14 localizes to both SPBs shortly after anaphase onset. In mid-to-late anaphase, levels of Cdc14 increase at the dSPB in both wildtype and bud14Δ cells. With mitotic exit, Cdc14 disappears from the dSPB in wildtype cells but not in bud14Δ cells. Accordingly, 50% of bud14Δ cells in G1 have Cdc14 at their SPBs. We also found that Cdc14 localization at the dSPB was largely, but not entirely, dependent on Bfa1 in bud14Δ cells. Furthermore, Bud14 interacted with Cdc14 in the Y2H system. Our results suggest that Glc7-Bud14 is part of a mechanism that promotes Cdc14 disappearance from the dSPB.

Direct and indirect selection in a proofreading polymerase.

The traits that affect evolvability are subject to indirect selection, as these traits affect the course of evolution over many generations rather than the direct replicative fitness of an individual. However, the evolution of evolvability-determining traits is often difficult to study because putative evolvability alleles often have confounding direct fitness effects of unknown origin and size. Here, we study theoretically and experimentally the evolution of mutation rates in proofreading polymerases with orthogonal control of direct and indirect selection. Mutagenic DNA polymerases enjoy a long-time fitness advantage by enhancing the rate of acquiring beneficial mutations. However, this is offset by a short-time fitness penalty, which we trace to a counterintuitive trade-off between mutation rates and activity in proofreading polymerases. Since these fitness effects act on different timescales, no one number characterizes the fitness of a mutator allele. We find unusual dynamic features in the resulting evolutionary dynamics, such as kinetic exclusion, selection by dynamic environments, and Rock-Paper-Scissors dynamics in the absence of ecology. Our work has implications for the evolution of mutation rates and more broadly, evolution in the context of an anti-correlation between mutation rates and short term fitness.

Current Overview of Spinocerebellar Ataxia Type 7 in Mexican Population: Challenges in Specialized Care for a Rare Disease.

Spinocerebellar ataxia type 7 (SCA7) is a rare genetic disease characterized by progressive cerebellar syndrome and macular degeneration. In a previous study, we clinically and genetically characterized a group of Mexican patients, which represented one of the largest cohorts of SCA7 patients worldwide and demonstrated that all patients had a unique genetic origin. Our laboratory developed a program for the diagnosis, medical care, and long-term follow-up of these patients living in Veracruz State, and in this report, we present an update to this research, covering 2013 to 2024. So far, we identified 172 SCA7 carriers, with a few cases outside Veracruz, and our data support that the length of the CAG repeat tract mainly determines disease severity and life expectancy, and accordingly, we define three different phenotypes, early-onset (EO), classical-onset (CO), and late-onset (LO), with EO patients showing the lowest life expectancy. Furthermore, we found that parental transmission of mutant alleles leads to increased CAG repeat instability, compared to maternal ones. Interestingly, a haplotype analysis revealed that patients outside Veracruz may have different genetic origins. In conclusion, longitudinal observations of SCA7 patients provide insight into the natural history of SCA7 and help to design strategies for diagnosis, genetic counseling, physical rehabilitation, and therapeutic alternatives.

A MSTNDel73C mutation with FGF5 knockout sheep by CRISPR/Cas9 promotes skeletal muscle myofiber hyperplasia.

Mutations in the well-known Myostatin (MSTN) produce a 'double-muscle' phenotype, which makes it commercially invaluable for improving livestock meat production and providing high-quality protein for humans. However, mutations at different loci of the MSTN often produce a variety of different phenotypes. In the current study, we increased the delivery ratio of Cas9 mRNA to sgRNA from the traditional 1:2 to 1:10, which improves the efficiency of the homozygous mutation of biallelic gene. Here, a MSTNDel73C mutation with FGF5 knockout sheep, in which the MSTN and FGF5 dual-gene biallelic homozygous mutations were produced via the deletion of 3-base pairs of AGC in the third exon of MSTN, resulting in cysteine-depleted at amino acid position 73, and the FGF5 double allele mutation led to inactivation of FGF5 gene. The MSTNDel73C mutation with FGF5 knockout sheep highlights a dominant 'double-muscle' phenotype, which can be stably inherited. Both F0 and F1 generation mutants highlight the excellent trait of high-yield meat with a smaller cross-sectional area and higher number of muscle fibers per unit area. Mechanistically, the MSTNDel73C mutation with FGF5 knockout mediated the activation of FOSL1 via the MEK-ERK-FOSL1 axis. The activated FOSL1 promotes skeletal muscle satellite cell proliferation and inhibits myogenic differentiation by inhibiting the expression of MyoD1, and resulting in smaller myotubes. In addition, activated ERK1/2 may inhibit the secondary fusion of myotubes by Ca2+-dependent CaMKII activation pathway, leading to myoblasts fusion to form smaller myotubes.

Preliminary investigation of MMP8 (rs11225395) and MMP9 (rs3787268) polymorphisms association with breast cancer risk in pashtun women of Pakistan.

Single Nucleotide polymorphisms (SNPs) in MMP8 and MMP9 have been widely associated with breast cancer risk in different ethnicities with inconsistent results. There is no such study conducted so far in the Pashtun population of Khyber Pakhtunkhwa, Pakistan. Therefore, this study was conducted to check MMP8 (rs11225395) and MMP9 (rs3787268) polymorphism with breast cancer risk in the selected population. This study, consisting of 300 breast cancer patients and 168 gender and age-matched healthy controls was subjected to confirm MMP8 and MMP9 polymorphisms. Clinicopathological data and blood samples were taken from all the participants. DNA was extracted and SNPs were confirmed using the T-ARMS-PCR protocol. Based on our study results, significant associations were observed between the MMP8 rs11225395 risk allele (G) and increased breast cancer risk, with the G allele frequency higher in patients (65%) compared to controls (51%) (OR = 1.752, 95% CI = 1.423-3.662, p = 0.002). Genotypes GG (OR = 4.218, p = 0.005) and AG (OR = 7.286, p = 0.0001) of MMP8 rs11225395 were also significantly associated with elevated breast cancer risk. Similarly, MMP9 rs3787268 exhibited a higher frequency of the risk allele (A) in breast cancer cases (81%) compared to controls (41%), correlating strongly with increased risk (OR = 6.320, p = 0.0001). Genotypes AA (OR = 14.500, p = 0.0001) and AG (OR = 2.429, p = 0.077) of MMP9 rs3787268 containing the risk allele showed significant associations with heightened breast cancer risk. Subgroup analyses based on age, disease progression, tumor size, and grade revealed noteworthy associations for both MMP8 rs11225395 and MMP9 rs3787268. MMP8 rs11225395 genotypes displayed significant correlations with age (p = 0.066), disease progression (p = 0.0001), larger tumor size (p = 0.005), and higher tumor grade (p = 0.006). Similarly, MMP9 rs3787268 genotypes were significantly associated with age (p = 0.001), disease progression (p = 0.010), larger tumor size (p = 0.018), and higher tumor grade (p = 0.037). Logistic regression analyses further underscored these genetic variants' potential role as biomarkers in breast cancer, particularly in relation to specific hormone receptor statuses such as estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) positivity. The results revealed significant associations between the mutant alleles and genotypes of MMP8 (rs11225395) and MMP9 (rs3787268) with increased breast cancer risk in the Pashtun population of Khyber Pakhtunkhwa, Pakistan. However, more investigation will be required on large data sets to confirm the selected SNPs and other SNPs in the selected and other related genes with the risk of breast cancer.

Field-scale gene flow of fungicide resistance in Pyrenophora teres f. teres and the effect of selection pressure on the population structure.

The effectiveness of fungicides to control foliar fungal crop diseases is being diminished by the increasing spread of resistances to fungicides. One approach that may help to maintain efficacy is remediation of resistant populations by sensitive ones. However, the success of such approaches can be compromised by re-incursion of resistance through aerial spore dispersal; although, knowledge of localized gene flow is lacking. Here, we report on a replicated mark-release-recapture field experiment with several treatments set up to study spore-dispersal-mediated gene flow of a mutated allele that confers demethylase inhibitor resistance in Pyrenophora teres f. teres (Ptt). Artificial inoculation of the host, barley (Hordeum vulgare), was successful across the 12-ha trial, where the introduced sensitive- and resistant-populations were, respectively, 6- and 13-fold the DNA concentration of the native Ptt population. Subsequent disease pressure remained low which hampered spread of the epidemic to such extent that gene flow was not detected at, or beyond 2.5 m from source points. In the absence of gene flow, plots were assessed for treatment effects; fungicide applied to populations that contained 14.3% of allele mutation increased in frequency to 24.5%, whereas sensitive populations had no change in structure. Untreated controls of native Ptt population remained genetically stable, yet untreated controls that were inoculated with sensitive Ptt had half the resistance frequency of the native population structure. The trial demonstrates the potential for management to remediate fungicide resistant pathogen populations, where localized gene flow is minimal; to safeguard chemical crop protection into the future.

A prioritization tool for cilia-associated genes and their in vivo resources unveils new avenues for ciliopathy research.

Defects in ciliary signaling or mutations in proteins that localize to primary cilia lead to a class of human diseases known as ciliopathies. Approximately 10% of mammalian genes encode cilia-associated proteins, and a major gap in the cilia research field is knowing which genes to prioritize to study and finding the in vivo vertebrate mutant alleles and reagents available for their study. Here, we present a unified resource listing the cilia-associated human genes cross referenced to available mouse and zebrafish mutant alleles, and their associated phenotypes, as well as expression data in the kidney and functional data for vertebrate Hedgehog signaling. This resource empowers researchers to easily sort and filter genes based on their own expertise and priorities, cross reference with newly generated -omics datasets, and quickly find in vivo resources and phenotypes associated with a gene of interest.

Biofortifying multiple micronutrients and decreasing arsenic accumulation in rice grain simultaneously by expressing a mutant allele of OAS-TL gene.

Rice grains typically contain relatively high levels of toxic arsenic (As) but low levels of essential micronutrients. Biofortification of essential micronutrients while decreasing As accumulation in rice would benefit human nutrition and health. We generated transgenic rice expressing a gain-of-function mutant allele astol1 driven by the OsGPX1 promoter. astol1 encodes a plastid-localized O-acetylserine (thiol) lyase (OAS-TL) with Ser189Asn substitution (OsASTOL1S189N), which enhances cysteine biosynthesis by forming an indissociable cysteine synthase complex with its partner serine acetyltransferase (SAT). The effects on growth, As tolerance, and nutrient and As accumulation in rice grain were evaluated in hydroponic, pot and field experiments. The expression of OsASTOL1S189N in pOsGPX1::astol1 transgenic lines enhanced SAT activity, sulphate uptake, biosynthesis of cysteine, glutathione, phytochelatins and nicotianamine, and enhanced tolerance to As. The expression of OsASTOL1S189N decreased As accumulation while increased the accumulation of multiple macronutrients (especially sulphur, nitrogen and potassium) and micronutrients (especially zinc and selenium) in rice grain in a pot experiment and two field experiments, and had little effect on plant growth and grain yield. Our study provides a new strategy to genetically engineer rice to biofortify multiple essential nutrients, reducing As accumulation in rice grain and enhancing As tolerance simultaneously.

Association of RIPK1 and RIPK2 Gene Polymorphisms with Rheumatoid Arthritis in a Chinese Han Population.

Rheumatoid arthritis (RA) is a systemic autoimmune disease with an obscure pathogenesis. This study aims to identify the susceptibility conferred by specific single nucleotide polymorphisms (SNPs), namely rs17548629 within the RIPK1 gene and rs10094579 within the RIPK2 gene, in RA. Additionally, it investigates the associations between inflammatory markers and biochemical parameters at various stages of the disease. We analyzed 394 patients with RA and 258 normal controls (NCs), examining SNPs within the RIPK1 (rs17548629) and RIPK2 (rs10094579) genes using polymerase chain reaction (PCR) and sequencing techniques. Profiles of RA patients were evaluated for inflammatory markers, including C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), as well as biochemical parameters such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), urea, glucose, uric acid, and creatinine. Additionally, disease-specific indicators included cyclic citrullinated peptide (CCP), rheumatoid factor (RF), antinuclear antibodies (ANA), and anti-keratin antibodies. The Disease Activity Score 28 (DAS28), based on ESR, was used to categorize RA patients into groups of high, moderate, or low disease activity. We found a significant association between the RIPK1 rs17548629 genotype and RA in the additive model (p < 0.001; OR = 3.23), over-dominant model (p < 0.001; OR = 0.27), and dominant model (p < 0.001; OR = 3.94). The frequency of the C allele at rs17548629 was significantly higher in NCs than in RA patients (p < 0.001; OR = 0.322). When compared with normal controls, the RIPK1 rs17548629 genotype demonstrated significant associations with both anti-CCP-positive RA patients (p < 0.001) and anti-CCP-negative RA patients (p < 0.001). Similarly, this genotype was associated with RF-positive RA patients (p < 0.001). Furthermore, the RIPK2 rs10094579 genotype was significantly associated with CRP levels in RA patients with low disease activity in the over-dominant model (p = 0.029; OR = 0.065, adjusted for age and sex). The presence of the RIPK1 rs17548629 genotype is associated with RA under additive, co-dominant, and dominant models. The T allele mutation at rs17548629 increases the risk of RA in the Chinese population. The RIPK1 rs17548629 genotype was identified as being associated with RF-positive RA patients, whereas no significant association was observed in RF-negative individuals. These findings suggest that this SNP may modulate the risk of RA in an RF-dependent manner. Furthermore, the RIPK2 rs10094579 genotype correlates with CRP levels in RA patients exhibiting low disease activity. This association underscores the necessity for caution when reducing the dosage of therapy in RA patients with low disease activity who carry the CA genotype at RIPK2 rs10094579. Additional research is warranted to explore other genotypes that may influence RA susceptibility and to refine potential treatment strategies.

Integrating allele-specific PCR with CRISPR-Cas13a for sensitive KRAS mutation detection in pancreatic cancer

BackgroundThe clustered regulatory interspaced short palindromic repeats (CRISPR)-Cas13a system has strong potential for highly sensitive detection of exogenous sequences. The detection of KRASG12 point mutations with low allele frequencies may prove powerful for the formal diagnosis of pancreatic ductal adenocarcinoma (PDAC).ResultsWe implemented preamplification of KRAS alleles (wild-type and mutant) to reveal the presence of mutant KRAS with CRISPR-Cas13a. The discrimination of KRASG12D from KRASWT was poor for the generic KRAS preamplification templates and depended on the crRNA design, the secondary structure of the target templates, and the nature of the mismatches between the guide and the templates. To improve the specificity, we used an allele-specific PCR preamplification method called CASPER (Cas13a Allele-Specific PCR Enzyme Recognition). CASPER enabled specific and sensitive detection of KRASG12D with low DNA input. CASPER detected KRAS mutations in DNA extracted from patients’ pancreatic ultrasound-guided fine-needle aspiration fluid.ConclusionCASPER is easy to implement and is a versatile and reliable method that is virtually adaptable to any point mutation.

Detection of the IDH1/2 Gene Mutations in Tumor Samples with Low-Abundance Mutant Allele

Detection of the IDH1/2 Gene Mutations in Tumor Samples with Low-Abundance Mutant Allele

Characteristics and predictors of cardiovascular events related to CYP2C19 gene polymorphisms following acute coronary syndrome.

Cardiovascular events prognosis based on CYP2C19 gene polymorphisms had many applications in clinical practice. Assessed characteristics and predictive performance of cardiovascular events in acute coronary syndrome patients with CYP2C19 gene polymorphisms. The patients were analyzed for CYP2C19 gene polymorphisms by real-time polymerase chain reaction (PCR). The PCR worked with primers around the mutant, as well as two fluorescent probes, one specific for the normal allele and the other for the mutant allele, and cardiovascular events were followed at 3 months and 6 months. Patients with CYP2C19 gene polymorphism accounted for 48.6% of which CYP2C19 *1/*2 genotype had the highest proportion (31.7%). The normal metabolizer phenotype was the majority (51.4%), and the *1 allele proportion accounted for the most (72.2%). Patients with type 2 diabetes (HR: 3.082, 95% CI: 1.652-5.747, p < 0.001) and ST-segment elevation myocardial infarction (HR: 2.874, 95% CI: 1.528-5.404, p = 0.001) were independent prognostic factors for cardiovascular events at 90 days. Type 2 diabetes was an independent prognostic factor for cardiovascular events at 180 days (HR: 3.714, 95% CI: 1.557-8.862, p = 0.003). The CYP2C19 gene polymorphism was an independent prognostic factor of cardiovascular events at 90 days (HR: 1.965, 95% CI: 1.012-3.814, p = 0.046). However, at 180 days of analysis, the association between the CYP2C19 gene polymorphism was not significant (HR: 2.234, 95% CI: 0.862-5.789, p = 0.098). CYP2C19 gene polymorphism was an independent prognostic factor of cardiovascular events 90 days after acute coronary syndrome.

Investigating the effects of a cryptic splice site in the En2 splice acceptor sequence used in the IKMC knockout-first alleles

Targeted mouse mutants are a common tool used to investigate gene function. The International Knockout Mouse Consortium undertook a large-scale screen of mouse mutants, making use of the knockout-first allele design that contains the En2 splice acceptor sequence coupled to the lacZ reporter gene. Although the knockout-first allele was designed to interfere with splicing and thus disrupt gene function, the En2 sequence has been reported to be transcribed within the host gene mRNA due to a cryptic splice site within the En2 sequence which allows splicing to the next exon of the host gene. In some circumstances, this has the potential to permit translation of a mutant protein. Here, we describe our computational analysis of all the mouse protein-coding genes with established knockout-first embryonic stem cell lines, and our predictions of their transcription outcome should the En2 sequence be included. As part of the large-scale mutagenesis program, mutant mice underwent a broad phenotyping screen, and their phenotypes are available. No wide-scale effects on mouse phenotypes reported were found as a result of the predicted En2 insertion. However, the En2 insertion was found experimentally in the transcripts of 24 of 35 mutant alleles examined, including the five already described, two with evidence of readthrough. Splicing from the cryptic splice site also has the potential to disrupt expression of the lacZ reporter gene. It is recommended that mutant transcripts be checked for this insertion as well as for leaky transcription in studies involving knockout-first alleles.

Frequency of chloroquine-resistant haplotype of Plasmodium falciparum (CVIET) in Ibadan, Southwest Nigeria 17 years post-chloroquine withdrawal

The replacement of chloroquine with artemisinin-based combination therapies (ACTs) for over a decade has had varying impacts on the ability of the malaria parasite to sustain its chloroquine resistance prowess in different malaria-endemic regions. We evaluated the frequency of Plasmodium falciparum chloroquine resistance transporter (PfCRT) mutations in Ibadan, Nigeria 17 years after the replacement of chloroquine with ACTs for malaria treatment. Fragments of PfCRT gene from genomic DNA of microscopically confirmed P. falciparum-infected patients were amplified and sequenced. There were 19% CVIET mutant and 81% CVMNK wild-type haplotypes on residues 72–76. A220S change were found in 16.7% of samples occurring concurrently with the CVIET haplotype, while a Q271E mutation occurred in a PfCRT wild-type isolate. The reduced prevalence of the PfCRT mutant alleles in this study compared to previous reports suggests a gradual disappearance of chloroquine-resistant malaria parasites following reduced drug pressure. It may also be a result of fitness demand on the parasites in attempts to evolve resistance against the current first-line regimen. However, evaluating the prevalence of other chloroquine resistance markers such as Plasmodium falciparum multidrug resistance 1 gene mutations in this population, and a more robust sample size will help to consolidate these findings.

Metabolic and genetic basis of liver damage in mechanical jaundice of non-tumor genesis in obstractive cholangitis or biliary pancreatitis

Aim. Establishment of versatile mechanisms behind liver damage in mechanical jaundice of non-tumor genesis combined with acute obstructive cholangitis or acute biliary pancreatitis.Materials and methods. In total, 64 cases of mechanical jaundice developed against the background of cholelithiasis were studied. Group 1 included 30 patients with mechanical jaundice combined with cholangitis; group 2 included 34 patients with acute biliary pancreatitis. Bile duct reconstruction was performed by an open method followed by standardized treatment. The intensity of membrane lipid peroxidation was determined by the level of diene conjugates, malonic dialdehyde, superoxide dismutase activity, and the activity of phospholipase A2. The severity of endotoxemia was estimated; a molecular-genetic test of the polymorphism of antioxidant system genes was performed.Results. The significance of the gene polymorphism of antioxidant enzymes in the formation of systemic alterative phenomena and severity of liver damage in mechanical jaundice complicated by cholangitis or acute pancreatitis was determined by allocation of patient subgroups depending on the presence of mutant allele T in the gene of superoxide dismutase SOD2 (C1147T). The groups of patients with the presence of such polymorphism, regardless of the combined diseases, demonstrated more pronounced and prolonged liver functional disorders and homeostasis disorders after restoration of biliary tract patency.Conclusion. The presence of mutant alleles of the SOD2 gene (C47T) in patients with non-tumor mechanical jaundice combined with acute cholangitis or pancreatitis is associated with an increase in the intensity of damage mechanisms at the systemic level, primarily with membrane lipid peroxidation, which correlates with the severity of liver damage (r = 0.834–0.967; p &lt; 0.05).