Mutation spectrum and enzyme profiling of G6PD deficiency in neonates of north India: a prospective study.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is a common X-linked disorder with well-established clinical and allelic heterogeneity and ethnic disparity. With ~390,000 annual births with G6PD deficiency in India, it emerges as the most predictable and preventable inbornmetabolic error. Disease prevalence and mutation spectrum have been reasonably reported fromcentral, western and southern parts of India and are mostly retrospective studies.Although prevalence data fromnorth India is available, there is paucity of data on the mutation spectrum and genotype-phenotype correlation (GxP). Thus, we aimed at establishing the clinical and mutation profiles for G6PD, as a part of a large prospective newborn screening study conducted between 2014 and 2016 across hospitals in Delhi, India. G6PD activity levels were measured at 24-48 h of life for ~200,000 neonates using Victor 2D and/or Genomic Screening Processor followed by confirmatory spectrophotometric analysis usingRBClysates of the respective neonates based on clinical symptoms.Asubset of 570 enzyme deficient neonates were screened formutations by polymerase chain reaction-restriction fragment length polymorphismand/or Sanger sequencing.Mediterraneanwas the most common mutation (n=318; 55.8%) with the lowest enzyme activity and most severe phenotype, followed by G6PD Orissa (n=187;32.8%); Kerala-Kalyan (n=25); Jammu (n=24);Mahidol (n=14); Chattam(n=1) andNilgiri/Coimbra (n=1).Of the 163 intramural neonates followed up, 68 developed clinical jaundice. However, no correlation was observed between jaundice and enzyme level. Notable outcome of this first ever prospective screening approach for G6PD deficiency in neonates may help in prediction of disease severity and appropriate timely management.

Perspectives on Rapid Antigen Tests for Downstream Validation and Development of Theranostics.

Point-of-care SARS-CoV-2 rapid antigen tests have proven to be useful over the years and have become more apparent to the public eye during COVID-19 pandemic due to their ease of use, rapid processing and result times, and low cost. Here, we have assessed the effectiveness and accuracy of rapid antigen tests in comparison to the standard real-time polymerase chain reaction analyses of the same samples.

Development of Flow Injection Analysis Method for the Second-Tier Estimation of Succinylacetone in Dried Blood Spot of Newborn Screening.

Tyrosinemia type 1 (TYR1) is a devastating aminoacidopathy, leading to mortality without medical intervention. Although, detection and quantification of tyrosine in dried blood spot (DBS) is possible, but being a non-specific marker for TYR1 and its frequent association with transient neonatal tyrosinemia limits its applicability. Despite, Succinylacetone (SUAC) being a pathognomonic marker for TYR1, but not often detectable by routine newborn screening (NBS). We envisaged to determine SUAC in DBS by an in-house flow injection analysis method on a liquid chromatography/tandem mass spectrometry (LC-MS/MS). Succinylacetone was eluted from the residual 3.2 mm DBS of primary NBS by an extraction solution containing acetonitrile-water-formic acid mixture containing stable-isotope labelled internal standard (IS) for SUAC and hydrazine. Detection and quantification was performed by the mass spectrometer using multiple reaction monitoring mode at m/z 155.1 → 109.1 for SUAC and m/z 160.1 → 114.1 for the SUAC IS. The assay was linear over a calibration range of 0.122-117.434 µmol/L. The Intra-day and Inter-day precision and accuracy for the assay was determined at two different levels of SUAC (2.542 µmol/L and 14.641 µmol/L), which showed a coefficient of variation of (6.91% and 12.65%) and (8.57% and 12.27%) respectively. The accuracy also ranged between 101.2 and 103.87%.This method provided the necessary sensitivity, precision, accuracy, recovery and linearity and hence, has the potential to reduce the false positive, false negative results which significantly minimise the cost involved in the screening and follow up of TYR1 patients. SUPPLEMENTARY INFORMATION: The online version of this article (10.1007/s12291-020-00944-z) contains supplementary material, which is available to authorized users.

Genetic alteration of Exon 5 of the PTEN gene in Indian patients with ameloblastoma.

OBJECTIVE: The PI3K/Akt/mTOR pathway is one of the signaling pathways associated with the pathogenesis of ameloblastoma. The phosphatase and tensin (PTEN) homologue controls cell migration and proliferation. It monitors the level of Akt and maintains cellular integrity. The aim of the present study was to study the genetic alteration of Exon 5 of the PTEN gene in Indian patients with ameloblastoma. STUDY DESIGN: Total DNA was extracted from formalin-fixed paraffin-embedded tissue samples from 20 cases with solid multicystic ameloblastoma (SMA) and from 10 cases with normal tooth germ. Exon 5 of the PTEN gene, was assessed for its role in the pathogenesis of ameloblastoma. RESULTS: Five of 20 cases of SMA showed genetic alteration. Of these cases 3 (15%) showed silent mutation, 1 (5%) showed change in amino acid sequence from valine to glutamic acid, and 1 (5%) showed nonsense-mediated mRNA decay. CONCLUSIONS: The present study showed 25% somatic mutational frequency in exonic region 5 of the PTEN gene. This may indicate its role in the pathogenesis of ameloblastoma.

HLA-DQA1 & DQB1 variants associated with hepatitis B virus-related chronic hepatitis, cirrhosis & hepatocellular carcinoma.

Background & objectives: Clinical outcome after hepatitis B virus (HBV) exposure varies extremely from spontaneous clearance to chronic hepatitis B and often progresses to liver cirrhosis (LC) and hepatocellular carcinoma (HCC). Host genetic factor plays an important role in the regulation of immune response. This study was aimed to investigate whether HLA class II DQA1 and DQB1 gene polymorphism were associated with chronic hepatitis B infection and in the development of HBV-related LC and HCC. Methods: DQA1 and DQB1 allele polymorphism were studied in 187 patients with HBV-related liver diseases (which included 73 chronic hepatitis B, 84 LC and 30 HCC patients) and 109 controls who had spontaneously recovered from HBV infection using polymerase chain reaction amplification with sequence-specific primers. Results: Our data suggested that DQA1*0101/2/4 [odds ratio (OR)=2.78; Pc=0.003], DQA1*0103 (OR=2.64; Pc=0.0007) and DQB1*0302/3 (OR=2.15; Pc=0.01) were associated with the protection from chronic HBV infection, whereas DQB1*0402 (OR=0.25; Pc=0.001) showed susceptible effect on chronic HBV infection. DQB1*0601 (OR=3.73; Pc=0.006) conferred protective effect from developing LC; similarly, DQB1*0302/3 (OR=5.53; Pc=0.05) and DQB1*0402 (OR=0.00; Pc=0.001) conferred protective effect from developing HCC. However, DQA1*0601 and DQB1*0503 showed susceptible effect on chronic HBV infection; these associations were no longer significant after Bonferroni correction. Interpretation & conclusions: Our results revealed HLA-DQA1*0101/2/4 - DQA1*0103 - DQB1*0302/3 and DQB1*0601 as protective and DQB1*0402 as risk alleles. The study suggests that various subtypes of HLA-DQA1 and DQB1 are associated with both HBV clearance and development of chronic HBV infections.

Cytogenetic Analysis for Suspected Chromosomal Abnormalities; A Five Years Experience.

INTRODUCTION: Chromosomal abnormalities are the results of alterations in the number or structure of chromosomes causing significant human morbidity and mortality. They are responsible for a large proportion of miscarriages, developmental delay, disorders of sexual development, congenital malformations and mental retardation. AIM: The aim of this study was to describe the prevalence of different chromosomal abnormalities in North Indian patients referred for cytogenetic analysis. MATERIALS AND METHODS: Total of 859 patients ranging from newborn to 37 years of age were referred to the division of genetics, Department of Paediatrics between 2010 and 2015, with a variety of clinical disorders; Down syndrome (DS), Turner's syndrome (TS) and Klinefelter syndrome; amenorrhea; ambiguous sex and multiple congenital malformations. Chromosomal analysis was performed on lymphocyte culture according to standard methods. RESULTS: Of the 859 cases studied, 371 (43.1%) had chromosomal abnormalities. The most common autosomal abnormalities were DS 302 (81.4%) and sex chromosomal abnormalities were TS 51 (13.7%). Numerical abnormalities were accounted for 353 (41.0%) and structural abnormalities 18 (2.0%), respectively. Various other chromosomal anomalies were also reported. CONCLUSION: We have reviewed the incidence and distribution of chromosomal abnormalities and found higher rate of chromosomal abnormalities 43.1% in the referred cases. Our data suggest that chromosomal analysis is important tool in the evaluation of genetic disorders and helps clinicians to provide accurate diagnosis and proper genetic counselling.

IL-18 polymorphisms in hepatitis B virus related liver disease.

Interleukine-18 (IL-18) was originally called interferon (INF-γ) inducing factor and plays a critical dual role in Th1 polarization and viral clearance. We aimed to explore whether single-nucleotide promoter polymorphisms (SNPs) are associated with the outcome of hepatitis B virus (HBV) infection. 271 HBV infected patients were recruited in this study out of these 109 were spontaneously recovered and 162 were diagnosed to be having persistent HBV infection which includes 48 chronic hepatitis, 84 liver cirrhosis, 30 HCC cases and were compared with 280 healthy controls. IL-18 promoter genotyping was performed with sequence-specific primers. The results demonstrated the significant involvement of genotype AA at position -607 in healthy controls (38.6%) when compared to cases (26.0%) (OR=0.54 (0.385-0.797)) and also associated with spontaneous clearance (37.6%) compared to persistent HBV infections (17.9%) (OR=2.76 (1.582-4.832)). Whereas, genotype CC at position -607 in cases (18.0%) when compared to healthy controls (6.7%) (OR=3.03 (1.734-5.303)) also associated with persistent HBV infections (24.1%) compared to spontaneous clearance (9.2%) (OR=0.31 (0.151-0.67)). And genotype GC at position -137 in cases (49.5%) compared to healthy controls (38.5%) (OR=1.55 (1.11-2.18)). Whereas, genotype GG at position -137 in healthy controls (56.8%) compared to cases (45.4%) (OR=0.63 (0.451-0.885)). No significant difference at position -137 was observed between spontaneous clearance and persistent HBV infections. These polymorphisms of the IL-18 gene promoter region at position -607 and -137 could be associated with different outcomes of HBV infection. The people with allele A at position -607 may be protected against HBV infection; moreover AA genotype is associated with spontaneous clearance.

Genetic polymorphism of interleukin-18 gene promoter region in rheumatoid arthritis patients from southern India.

BACKGROUND: Interleukin-18 (IL-18) is a pro inflammatory cytokine which plays a key role in the acute and chronic inflammatory phases of Rheumatoid Arthritis (RA). The Single Nucleotide Polymorphisms (SNPs) of IL-18 gene promoter region at positions -137 and -607, are postulated to be associated with RA. To test this, this study aimed to identify the association between these SNPs of the IL-18 gene promoter region of RA in south Indian patients. MATERIALS AND METHODS: This study was carried on 190 subjects among which 90 were RA patients and 100 were age and sex matched controls. Genomic DNA was extracted by Salting out method. IL 18 gene promotor region SNPs, IL 18 - 607 and IL 18 -137 were amplified by using sequence specific primers. The amplified products of different samples were separated by using a 1.5% agarose gel, stained with ethidium bromide and photographed. All statistical analyses were carried out by using SYSTAT 12 software. RESULTS: At position 607, the frequencies of C allele, CC genotype, A allele and AA genotype were found to be significantly higher in patients and controls respectively and there was no significant difference in CA genotype. At position 137, there was no significant difference between the two groups with regard to G and C allelles but there was a significant increase in GG genotype of patients and CC genotype of controls. There was no association between duration of morning stiffness, rheumatoid factor positivity or negativity, age of onset and gender with distribution of genotypes and alleles. CONCLUSION: C allele, CC genotype at position-607 and GG genotype at position-137 are risk factors and A allele, AA genotype at position-607 and CC genotype at position-137 have protective effect for RA.

Association of Methylene Tetrahydrofolate Reductase Polymorphism with BMD and Homocysteine in Premenopausal North Indian Women.

BACKGROUND AND AIM: Osteoporosis (OP) is a common nutrigenomic disease associated with various genetic components. Observational studies have indicated that mildly elevated homocysteine was a strong risk factor for osteoporotic fractures. Yet there is no clear biologic mechanism for an effect of homocysteine on bone.The aim of this study was to investigate the association of MTHFR C677T and A1298C polymorphisms, and to verify the association of these polymorphisms with bone mineral density and homocysteine in premenopausal women of northern India. MATERIAL AND METHODS: We included 402 north Indian patients with altered BMD, both Osteopenic (OPN) and Osteoporosis, and normal controls. Genotype identification for MTHFR C677T and A1298C polymorphisms were analyzed by PCR-RFLP method, correlated with Bone Mineral Density (BMD), Homocysteine (Hcy), Folate and Vitamin B12. RESULTS: The study groups did not differ in terms of age, weight and body mass indices. Prevalence of Genotype frequencies (GFs) for MTHFRC677T OP were (n: 402): CC 361 (89.8%), CT 25 (6.22%), TT 16 (3.98%) and that for MTHFR A1298C were (n: 402) AA 353(87.81%), AC 29(7.21%), CC 20(4.98%). Folate was significantly lower in the OP group than those in both the other groups, while there was no significant difference in Hcy in the OP group relative to OPN, as compared to controls. CONCLUSION: The GFs for MTHFR C677T and A1298C polymorphisms were not different between both groups. In conclusion, polymorphism of the MTHFR 677T is associated with small differences in BMD with folate levels. Further, more investigations should be done in larger studies for other epigenetic pathways, that may increase the risk of Osteoporosis.

Duration of hepatitis E viremia in pregnancy.

OBJECTIVE: To investigate the duration of hepatitis E virus (HEV) infection in pregnant and non-pregnant women with acute viral hepatitis (AVH) or fulminant hepatic failure (FHF). METHODS: A prospective study conducted with 20 pregnant women with AVH, 20 non-pregnant women with AVH, 10 pregnant women with FHF, and 9 non-pregnant women with FHF-all with HEV infection. The women were followed up on day 7, 15, 30, 60, and 90 following recruitment for the presence of HEV-RNA. RESULTS: Of the 59 patients with HEV infection, only 2 (3.4%) revealed HEV viremia at day 30 and none of the patients was viremic at day 60 and day 90. The proportion of HEV viremia in pregnant women with AVH and FHF at day 15 was significantly higher than in non-pregnant women (88.3% vs 27.6%; P<0.001). Similarly, HEV viremia among patients with AVH was significantly higher in pregnant women compared with non-pregnant women (100% vs 55%; P<0.001). CONCLUSION: HEV viremia may be prolonged in pregnancy.