Correlation of the Geriatric Assessment with Overall Survival in Older Patients with Cancer

AIMS

Global guidelines recommend that all older patients with cancer receiving chemotherapy should undergo a geriatric assessment. However, utilisation of the geriatric assessment is often constrained by its time-intensive nature, which limits its adoption in settings with limited resources and high demand. There is a lack of evidence correlating the results of the geriatric assessment with survival from the Indian subcontinent. Therefore, the aims of the present study were to assess the impact of the geriatric assessment on survival in older Indian patients with cancer and to identify the factors associated with survival in these older patients.

MATERIALS AND METHODS

This was an observational study, conducted in the geriatric oncology clinic of the Tata Memorial Hospital (Mumbai, India). Patients aged 60 years and older with cancer who underwent a geriatric assessment were enrolled. We assessed the non-oncological geriatric domains of function and falls, nutrition, comorbidities, cognition, psychology, social support and medications. Patients exhibiting impairment in two or more domains were classified as frail.

RESULTS

Between June 2018 and January 2022, we enrolled 897 patients. The median age was 69 (interquartile range 65-73) years. The common malignancies were lung (40.5%), oesophagus (31.9%) and genitourinary (12.1%); 54.6% had metastatic disease. Based on the results of the geriatric assessment, 767 (85.4%) patients were frail. The estimated median overall survival in fit patients was 24.3 (95% confidence interval 18.2-not reached) months, compared with 11.2 (10.1-12.8) months in frail patients (hazard ratio 0.54; 95% confidence interval 0.41-0.72, P < 0.001). This difference in overall survival remained significant after adjusting for age, sex, primary tumour and metastatic status (hazard ratio 0.56; 95% confidence interval 0.41-0.74, P < 0.001). In the patients with a performance status of 0 or 1 (n = 454), 365 (80.4%) were frail; the median overall survival in the performance status 0-1 group was 33.0 months (95% confidence interval 24.31-not reached) in the fit group versus 14.4 months (95% confidence interval 12.25-18.73) in the frail patients (hazard ratio 0.50; 95% confidence interval 0.34-0.74, P = 0.001). In the multivariate analysis, the geriatric assessment domains that were predictive of survival were function (hazard ratio 0.68; 95% confidence interval 0.52-0.88; P = 0.003), nutrition (hazard ratio 0.64; 95% confidence interval 0.48-0.85, P = 0.002) and cognition (hazard ratio 0.67; 95% confidence interval 0.49-0.91, P = 0.011).

DISCUSSION

The geriatric assessment is a powerful prognostic tool for survival among older Indian patients with cancer. The geriatric assessment is prognostic even in the cohort of patients thought to be the fittest, i.e. performance status 0 and 1. Our study re-emphasises the critical importance of the geriatric assessment in all older patients planned for cancer-directed therapy.

Defining anthropometric thresholds (mid-arm circumference and calf circumference) in older adults residing in the community: a cross-sectional analysis using data from the population representative Longitudinal Aging Study in India (LASI DAD)

OBJECTIVES

To identify factors associated with malnutrition (undernutrition and overnutrition) and determine appropriate cut-off values for mid-arm circumference (MAC) and calf circumference (CC) among community-dwelling Indian older adults.

DESIGN

Data from the first wave of harmonised diagnostic assessment of dementia for Longitudinal Ageing Study in India (LASI-DAD) were used. Various sociodemographic factors, comorbidities, geriatric syndromes, childhood financial and health status were included. Anthropometric measurements included body mass index (BMI), MAC and CC.

SETTING

Nationally representative cohort study including 36 Indian states and union territories.

PARTICIPANTS

4096 older adults aged >60 years from LASI DAD.

OUTCOME MEASURES

The outcome variable was BMI, categorised as low (<18.5 kg/m2), normal (18.5-22.9 kg/m2) and high (>23 kg/m2). The cut-off values of MAC and CC were derived using ROC curve with BMI as the gold standard.

RESULTS

902 (weighted percentage 20.55%) had low BMI, 1742 (44.25%) had high BMI. Undernutrition was associated with age, wealth-quintile and impaired cognition, while overnutrition was associated with higher education, urban living and comorbidities such as hypertension, diabetes and chronic heart disease. For CC, the optimal lower and upper cut-offs for males were 28.1 cm and >31.5 cm, respectively, while for females, the corresponding values were 26 cm and >29 cm. Similarly, the optimal lower and upper cut-offs for MAC in males were 23.9 cm and >26.9 cm, and for females, they were 22.5 cm and >25 cm.

CONCLUSION

Our study identifies a high BMI prevalence, especially among females, individuals with higher education, urban residents and those with comorbidities. We establish gender-specific MAC and CC cut-off values with significant implications for healthcare, policy and research. Tailored interventions can address undernutrition and overnutrition in older adults, enhancing standardised nutritional assessment and well-being.

The current status of geriatric oncology in India

Geriatric oncology in India is relatively new. The number of older persons with cancer is increasing exponentially; at our institution, 34% of patients registered are 60 years and over. Apart from the Tata Memorial Hospital in Mumbai, there are currently no other Indian centers that have a dedicated geriatric oncology unit. Geriatric assessments (GAs) are done sporadically, and older patients with cancer are usually assessed and treated based on clinical judgement. Challenges to increasing the uptake of GA include a lack of training/time/interest or knowledge of the importance of the GA. Other challenges include a lack of trained personnel with expertise in geriatric oncology, and a paucity of research studies that seek to advance the outcomes in older Indian patients with cancer. We anticipate that over the next 10 years, along with the inevitable increase in the number of older persons with cancer in India, there will be a commensurate increase in the number of skilled personnel to care for them. Key goals for the future include increased research output, increased number of dedicated geriatric oncology units across the country, India-specific geriatric oncology guidelines, geriatric oncology training programs, and a focus on collaborative work across India and with global partners. In this narrative review, we provide a broad overview of the status of geriatric oncology in India, along with a description of the work done at our center. We hope to spark interest and provide inspiration to readers to consider developing geriatric oncology services in other settings.

Validation of the Onco-MPI in predicting short-term mortality in older Indian patients with cancer

INTRODUCTION

The number of older patients with cancer is increasing exponentially worldwide, and a similar trend has also been noted in India. The Multidimensional Prognostic Index (MPI) strongly correlates the presence of individual comorbidities with mortality, and the Onco-MPI prognosticates patients accurately for overall mortality. However, limited studies have evaluated this index in patient populations beyond Italy. We evaluated the performance of the Onco-MPI index in predicting mortality in older Indian patients with cancer.

MATERIALS AND METHODS

This observational study was conducted between October 2019 and November 2021 in the Geriatric Oncology Clinic at Tata Memorial Hospital in Mumbai, India. The data of patients aged ≥60 years with solid tumors who underwent a comprehensive geriatric assessment was analysed. The study's primary aim was to calculate the Onco-MPI for patients in the study and correlate it with one-year mortality.

RESULTS

A total of 576 patients aged ≥60 years were included in the study. The median age (range) of the population was 68 (60-90) years, and 429 (74.5%) were male. After a median follow-up of 19.2 months, 366 (63.7%) patients had died. The proportion of patients classified as low risk (0-0.46), moderate risk (0.47-0.63) and high risk (0.64-1.0) were 38% (219 patients), 37% (211 patients) and 25% (145 patients), respectively. There was a significant difference in one-year mortality rates between the low-risk patients compared to medium and high-risk patients (40.6% vs 53.1% vs 71.7%; p < 0.001).

DISCUSSION

The current study validates the Onco-MPI as a predictive tool for estimating short-term mortality in older Indian patients with cancer. Further prospective studies need to build on this index to obtain a score with greater discrimination in the Indian population.

The chromosome-scale genome assembly of cluster bean provides molecular insight into edible gum (galactomannan) biosynthesis family genes

Cluster bean (Cyamopsis tetragonoloba (L.) Taub 2n = 14, is commonly known as Guar. Apart from being a vegetable crop, it is an abundant source of a natural hetero-polysaccharide called guar gum or galactomannan. Here, we are reporting a chromosome-scale reference genome assembly of a popular cluster bean cultivar RGC-936, by combining sequencing data from Illumina, 10X Genomics, Oxford Nanopore technologies. An initial assembly of 1580 scaffolds with an N50 value of 7.12 Mb was generated and these scaffolds were anchored to a high density SNP linkage map. Finally, a genome assembly of 550.31 Mb (94% of the estimated genome size of ~ 580 Mb (through flow cytometry) with 58 scaffolds was obtained, including 7 super scaffolds with a very high N50 value of 78.27 Mb. Phylogenetic analysis using single copy orthologs among 12 angiosperms showed that cluster bean shared a common ancestor with other legumes 80.6 MYA. No evidence of recent whole genome duplication event in cluster bean was found in our analysis. Further comparative transcriptomics analyses revealed pod-specific up-regulation of genes encoding enzymes involved in galactomannan biosynthesis. The high-quality chromosome-scale cluster bean genome assembly will facilitate understanding of the molecular basis of galactomannan biosynthesis and aid in genomics-assisted improvement of cluster bean.

Predictors of Survival Among the Oldest Old Following Acute Hospital Admission: Insights From Clinical and Biochemical Factors

Understanding the factors influencing survival in oldest old population is crucial for providing appropriate care and improving outcomes. This prospective observational study aimed to investigate the determinants of survival in acutely ill oldest old patients during acute hospitalization and 1-month follow-up. Various geriatric domains and biochemical markers were assessed. Among the 70 included patients with a median age of 87 (Inter quartile range: 85-90), the presence of diabetes, delirium, tachypnea, and high sirtuin-5 levels were associated with reduced in-hospital survival. Non-survivors had raised levels of Sirtuin 1 and Sirtuin 5, with an increase of 43% and 70%, respectively. At 1 month, delirium and diabetes were still associated with reduced survival. These findings suggest that type-2 diabetes, delirium, tachypnea, and high sirtuin-5 levels could serve as predictors of reduced survival in acutely ill, hospitalized oldest old patients.

Geriatric assessment as a predictor of survival among older Indian patients with cancer

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Background: ASCO guidelines recommend that geriatric assessment (GA) should be performed in all older adults with cancer. However, GA is labor- and time-intensive, hence the uptake is poor, especially in crowded resource poor-settings. There are no data correlating GA with overall survival (OS) outcomes from the Indian subcontinent. Methods: A prospective observational study in the geriatric oncology clinic of the Tata Memorial Hospital in Mumbai, India. Patients aged 60 years and above, with cancer who underwent a GA were enrolled. The domains assessed included: function (basic and instrumental activities of daily living, timed-up-and-go), nutrition (body mass index, unintentional weight loss, mini-nutritional assessment), comorbidities, cognition, psychological (depression, anxiety), social support, and medication (polypharmacy and potentially inappropriate medications). Patients with > 2 deranged GA domains were considered frail. Results: Between June 2018 and January 2022, 909 patients were enrolled. The median age was 69 (IQR, 60-88) years. Common malignancies included lung (40%), esophagus (21%) and head and neck (11%); 53% had metastatic disease. 80% had > 2 impaired domains in GA patients had vulnerabilities in a median of 3 (IQR, 0-5) domains. Median OS in fit patients based on the GA was 17.5 (95% CI, 13.9-21.0) months vs 12.1 (95% CI, 10.1-14.0) months in frail patients, (HR 0.66; 95% CI, 0.49-0.88, p = 0.005), which remained significant after adjusting for age, sex, and stage (HR, 0.71; 95% CI: 0.53-0.94, p = 0.021). In the multivariate analysis (Table), the domains that were predictive of survival were nutrition (HR: 0.65, 95% CI: 0.47-0.92, p = 0.014), cognition (HR: 0.65; 95% CI: 0.46-0.91, p = 0.012) and fatigue (HR: 0.74, 95% CI: 0.56-0.98, p = 0.038). Conclusions: In older Indian patients with cancer, GA is a powerful prognosticator of survival. In settings where a complete GA is not possible, nutrition, cognition, and fatigue should be the minimum domains assessed. Clinical trial information: CTRI/2020/04/024675. [Table: see text]

Prevalence and outcomes of frailty in older patients with cancer: A prospective study from geriatric oncology clinic

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Background: Frail older patients present with increased symptom burden, medical complexity and reduced tolerance to medical and surgical interventions. Data regarding the prevalence of frailty and its association with outcomes, such as overall survival, is limited from India. This study aimed to establish the prevalence of frailty and its association with overall survival (OS) in older patients with cancer. Methods: This was a prospective study conducted in geriatric oncology clinic of Tata memorial hospital (Mumbai India). Patients aged 60 years and above referred to the clinic were included. Frailty was identified using the Rockwoods Clinical frailty scale, and patients with a score of five or more were diagnosed as frail. Demographic details, type of cancer, stage and multi-domains geriatric assessment was done. Cancer and Ageing Research group online toxicity tool was used to assess the chemotherapy toxicity risk. A t-test or two-sample Wilcoxon rank-sum test was used to study the association between frailty status and non-categorical variables and the Pearson chi-squared test was used to measure the association between categorical variables. The Kaplan Meier survival estimation and the Cox proportional hazard model were used to perform the survival analysis. Results: Between June 2018 to January 2022, 909 patients were evaluated and 662 patients with clinical frailty score were included. The median age was 68 (60-86) years and 107 (16%) were above the age of 75 years. The most common malignancies were lung (39%), esophagus (21%) and head and neck (10%); 53% had metastatic disease. 192 (29%) were frail, and it prevalence increased with age. Frailty status was associated with poor OS (unadjusted HR: 2.512; 95% CI: 1.931-3.268). This association was significant even after adjusting for age, gender, BMI and stage of cancer (adjusted HR: 2.104; 95% CI: 1.598-2.770). Frailty was associated with comorbidities such as diabetes (32% vs 23%, p = 0.014), chronic obstructive pulmonary disease (13% vs 7%, p = 0.045) and cardiovascular disease (19% vs 12%, p = 0.017). Among the geriatric domains, frail patients had greater incidence of polypharmacy (52% vs 33%, p < 0.01), slower gait speed (53% vs 12%, p < 0.01), impaired cognition (25% vs 7%, p < 0.01), poor nutritional status (51% vs 17%, p < 0.001), depression (29% vs 8%, p < 0.01) and anxiety (14% vs 5%, p < 0.01). Conclusions: The prevalence of frailty among older cancer patients is high. It is associated with poor physical, cognitive and psychological resilience and is associated with poor overall survival. Our study supports the routine assessment of frailty in older patients with cancer to guide treatment decisions. Clinical trial information: CTRI/2020/04/024675.

Addressing the Needs of Older Adults With Cancer in Low- and Middle-Income Settings

The number of older adults in the world is projected to increase steeply over the next 30 years; most older adults will live in low- and middle-income countries. This will have a direct impact on the global cancer burden, as cancer is largely a disease of aging. A revolution in the way we care for older adults in low- and middle-income settings is needed to meet rapidly rising demands. Regardless of a nation's relative wealth or resources, implementing the geriatric assessment in cancer care has presented a challenge because of omission of the principles of geriatric oncology from formal training and continuing education, lack of time, and a shortage of qualified personnel. To meet the challenge of caring for older adults globally, we must: (1) re-imagine aging-focused training for providers and nurses, (2) create and strengthen collaborations/partnerships between geriatric oncology teams and aging-service organizations, and (3) increase advocacy for age-friendly health care policy. By harnessing technology, the reach of specialized oncology education and care can be extended even-or especially-to low- and middle-income settings.

Parkinsonism: An emerging post COVID sequelae

Parkinsonism has a complex and multifactorial aetiology and the role of post viral infection parkinsonism has been documented. The recent pandemic has made it clear that COVID-19 causes respiratory disease and affects multiple organs, which includes the central nervous system. Here we report three cases of post COVID parkinsonism occurring in older adults, age 60 years and above, and their response to levodopa-carbidopa.

Xanthogranulomatous pyelonephritis due to Aspergillus in a non-diabetic older patient

Xanthogranulomatous pyelonephritis is a rare condition characterised by destructive granulomatous inflammation of renal parenchyma. Primary renal Aspergillosis has been reported in patients with immunocompromised states such as diabetes, retroviral disease, organ transplant recipients, etc. We present a unique case of an older adult in his early 60s, presenting with fever and left flank pain with renal angle tenderness, diagnosed with primary renal aspergillosis with xanthogranulomatous pyelonephritis. These symptoms resolved with a long duration of antifungal (itraconazole) therapy and nephrectomy. The unique features are the development of fungal pyelonephritis in the absence of any immunocompromising conditions and the development of xanthogranulomatous changes with no risk factors.

Chemotactic factor inducing Interleukin-8 (IL8) gene is transcriptionally elevated in experimental enterotoxaemia in goats caused by Clostridium perfringens type D

The current study was designed to analyse the effects of experimental induction of enterotoxaemia through intra-duodenal inoculation of C. perfringens type D culture isolated from spontaneous outbreaks in goats. Twenty goats (6–9 month age) were divided into four groups and C. perfringens type D culture was inoculated intra-duodenally as per following: Group-I (whole cultures-WC), group-II (culture supernatant-CS), group-III (washed cells-WS), and group-IV (uninfected control-C). The treated animals were sacrificed after 72 h post infection (hpi), and necropsy showed gross changes including haemorrhages and congestion in the ileal and colon mucosa, pulmonary congestion and edema in lung. Kidney, brain and spleen exhibited severe to moderate congestion. Microscopic changes like haemorrhages, degenerative and necrotic changes in the mucosal epithelium of intestine and haemorrhages in kidney parenchyma were observed in the H&E stained sections. Lung alveolar sacs were filled with proteinaceous fluid. Immunohistochemistry revealed positive immunolabelling for etx (epsilon toxin) in the mucosa of intestine in WC and CS group. Control animals did not exhibit any significant gross or microscopic changes. PCR amplification of DNA extracted from intestinal tissues of WC and CS groups showed positive for etx gene demonstrating the production of epsilon toxin. Transcriptional responses in experimental groups were assessed by quantitative reverse transcription real time PCR (qRT-PCR). Genes including IL-1β and IL2 showed up-regulation in all the experimental groups (WC, CS&WS). Specifically the toxin-based experimental groups (WC&CS) showed up-regulation of the gene responsible for chemotaxis viz. IL-8, while the washed cells group (WS) showed higher transcriptional response to Cathepsin-L (Cat-L) gene denoting the acute inflammatory response due to neutrophil elastase activity. These results take a cue on the evolving nature of the enterotoxaemia in goats due to various strains circulating in the field. The host response and its modulation due to the novel enterotoxaemia strains throws light on the current challenges in efficient control of the disease in goats.

Case Report: Hypercalcemia in an Older Patient with Type I Lepra Reaction

Leprosy is a rare, chronic granulomatous disease, and India accounts for two-thirds of the new cases reported worldwide. Hypercalcemia is a rare complication of granulomatous disease. Here, we report a case of an older adult patient with leprosy and type I lepra reaction presenting with severe hypercalcemia.

Behavioural issues in late life may be the precursor of dementia- A cross sectional evidence from memory clinic of AIIMS, India

Background

Mild Behavioural Impairment (MBI), an “at risk” state for incident cognitive declin, is characterized by late onset, sustained neuropsychiatric symptoms of any severity which cannot be accounted for by other formal medical and psychiatric nosology. There is no study related to MBI from India.

Methods and findings

In this cross-sectional observational study 124 subjects 60 years and above were recruited between March 2017 to October 2018, from memory clinic of department of Geriatric medicine with memory or behavioural complains. Subjects with major neurocognitive impairment (CDR score of 1 or more), major depressive disorder, generalized anxiety disorder and impaired activities of daily living (ADL) were excluded. Subjects with Mild Cognitive impairment (MCI) (CDR- 0.5), and Subjective cognitive impairment (SCI) (CDR- 0) were included. Neuropsychiatric Inventory Questionnaire (NPI-Q) was used to identify the presence of NPS. The ISTAART-MBI (International Society of Advance Alzheimer’s Research and Treatment-Alzheimer’s Association) diagnostic criteria was used to diagnose MBI. All the participants underwent a geriatric assessment using standardised screening. The objectives of this study was to determine the frequency of mild behavioural impairment (MBI), and its domains, in MCI or SCI and its association with comorbidities and geriatric syndromes. The mean age of the participants was 69.21, 71.77% (89) were male and 28.23% (35) were female. 41.13% (51) of these individuals were diagnosed with MBI. The MBI and non MBI group differed significantly in marital status, cognitive status and MCI subtype. The proportion of domains involved are as follows: decreased motivation 60.78%(31), emotional dysregulation 54.90% (28), impulse dyscontrol 68.63% (35), social inappropriateness 21.57%(11), abnormal perception 2 (3.93%). Presence of multi-morbidity, and diabetes, were statistically significant between the groups.

Conclusion

This study presents the first clinic-based prevalence estimates of MBI from Asia. Findings indicate a relatively high prevalence of MBI in predementia clinical states, impulse dyscontrol was the most commonly involved MBI domain. Multimorbidity, diabetes, urinary incontinence were other determinants of MBI.

Identification and characterization of trait-specific SNPs using ddRAD sequencing in water buffalo

Single Nucleotide Polymorphism (SNP) is one of the important molecular markers widely used in animal breeding program for improvement of any desirable genetic traits. Considering this, the present study was carried out to identify, annotate and analyze the SNPs related to four important traits of buffalo viz. milk volume, age at first calving, post-partum cyclicity and feed conversion efficiency. We identified 246,495, 168,202, 74,136 and 194,747 genome-wide SNPs related to mentioned traits, respectively using ddRAD sequencing technique based on 85 samples of Murrah Buffaloes. Distribution of these SNPs were highest (61.69%) and lowest (1.78%) in intron and exon regions, respectively. Under coding regions, the SNPs for the four traits were further classified as synonymous (4697) and non-synonymous (3827). Moreover, Gene Ontology (GO) terms of identified genes assigned to various traits. These characterized SNPs will enhance the knowledge of cellular mechanism for enhancing productivity of water buffalo through molecular breeding.

Comparative transcriptome analysis reveals the genetic basis of coat color variation in Pashmina goat

The genetics of coat color variation remains a classic area. Earlier studies have focused on a limited number of genes involved in color determination; however, the complete set of trait determinants are still not well known. In this study, we used high-throughput sequencing technology to identify and characterize intricate interactions between genes that cause complex coat color variation in Changthangi Pashmina goats, producer of finest and costly commercial animal fiber. We systematically identified differentially expressed mRNAs and lncRNAs from black, brown and white Pashmina goat skin samples by using RNA-sequencing technique. A pairwise comparison of black, white and brown skin samples yielded 2479 significantly dysregulated genes (2422 mRNA and 57 lncRNAs). Differentially expressed genes were enriched in melanin biosynthesis, melanocyte differentiation, developmental pigmentation, melanosome transport activities GO terms. Our analysis suggested the potential role of lncRNAs on color coding mRNAs in cis and trans configuration. We have also developed online data repository as a component of the study to provide a central location for data access, visualization and interpretation accessible through http://pcd.skuastk.org/.

Unravelling the epigenomic interactions between parental inbreds resulting in an altered hybrid methylome in pigeonpea

DNA methylation is an important heritable landmark conferring epigenetic changes in hybrids and has fascinated biologists and plant-breeders over the years. Although epigenetic changes have been documented in rice and maize hybrids, such investigations have not been reported in pigeonpea. Here, we report genome-wide methylation profiles of pigeonpea sterile and fertile inbred lines and their fertile F1 hybrid at single base resolution. We found that pigeonpea genome is relatively enriched in CG methylation. Identification of differentially methylated regions (DMRs) in the sterile and fertile parent revealed remarkable differences between their methylation patterns. Investigation of methylation status of parental DMRs in hybrid revealed non-additive methylation patterns resulting from trans-chromosomal methylation and trans-chromosomal demethylation events. Furthermore, we discovered several DMRs negatively associated with gene expression in the hybrid and fertile parent. Interestingly, many of those DMRs belonged to transposable elements and genes encoding pentatricopeptide repeats associated proteins, which may mediate a role in modulating the genes impacting pollen fertility. Overall, our findings provide an understanding of two parental epigenomes interacting to give rise to an altered methylome in pigeonpea hybrids, from genome-wide point of view.

The complete mitochondrial genome of the Asian stinging catfish, Heteropneustes fossilis (Siluriformes, Heteropneustidae) and its comparison with other related fish species

The complete mitogenome of Heteropneustes fossilis is described using Ion Torrent (PGM sequencer), which showed it was 16,489 bp in size comprising 13 mRNAs, 22 tRNAs, 2 rRNA genes, and 858 bp as D-Loop control region, along with gene order and organization, being similar to most of the other related Siluriformes fish mitogenome of NCBI databases. The 20 RNAs were packed into a typical cloverleaf structure. The mitogenome in the present study has 99% similarity to the complete mitogenome sequence of H. fossilis mitogenome reported earlier and also would be helpful in understanding the population genetics, phylogenetics, and evolution of catfishes.

A computational approach for prediction of donor splice sites with improved accuracy

Identification of splice sites is important due to their key role in predicting the exon-intron structure of protein coding genes. Though several approaches have been developed for the prediction of splice sites, further improvement in the prediction accuracy will help predict gene structure more accurately. This paper presents a computational approach for prediction of donor splice sites with higher accuracy. In this approach, true and false splice sites were first encoded into numeric vectors and then used as input in artificial neural network (ANN), support vector machine (SVM) and random forest (RF) for prediction. ANN and SVM were found to perform equally and better than RF, while tested on HS3D and NN269 datasets. Further, the performance of ANN, SVM and RF were analyzed by using an independent test set of 50 genes and found that the prediction accuracy of ANN was higher than that of SVM and RF. All the predictors achieved higher accuracy while compared with the existing methods like NNsplice, MEM, MDD, WMM, MM1, FSPLICE, GeneID and ASSP, using the independent test set. We have also developed an online prediction server (PreDOSS) available at http://cabgrid.res.in:8080/predoss, for prediction of donor splice sites using the proposed approach.

Identification of species based on DNA barcode using k-mer feature vector and Random forest classifier

DNA barcoding is a molecular diagnostic method that allows automated and accurate identification of species based on a short and standardized fragment of DNA. To this end, an attempt has been made in this study to develop a computational approach for identifying the species by comparing its barcode with the barcode sequence of known species present in the reference library. Each barcode sequence was first mapped onto a numeric feature vector based on k-mer frequencies and then Random forest methodology was employed on the transformed dataset for species identification. The proposed approach outperformed similarity-based, tree-based, diagnostic-based approaches and found comparable with existing supervised learning based approaches in terms of species identification success rate, while compared using real and simulated datasets. Based on the proposed approach, an online web interface SPIDBAR has also been developed and made freely available at http://cabgrid.res.in:8080/spidbar/ for species identification by the taxonomists.

Mapping QTLs for Salt Tolerance in Rice (Oryza sativa L.) by Bulked Segregant Analysis of Recombinant Inbred Lines Using 50K SNP Chip

Soil salinity is a major constraint to rice production in large inland and coastal areas around the world. Modern high yielding rice varieties are particularly sensitive to high salt stress. There are salt tolerant landraces and traditional varieties of rice but with limited information on genomic regions (QTLs) and genes responsible for their tolerance. Here we describe a method for rapid identification of QTLs for reproductive stage salt tolerance in rice using bulked segregant analysis (BSA) of bi-parental recombinant inbred lines (RIL). The number of RILs required for the creation of two bulks with extreme phenotypes was optimized to be thirty each. The parents and bulks were genotyped using a 50K SNP chip to identify genomic regions showing homogeneity for contrasting alleles of polymorphic SNPs in the two bulks. The method was applied to ‘CSR11/MI48’ RILs segregating for reproductive stage salt tolerance. Genotyping of the parents and RIL bulks, made on the basis of salt sensitivity index for grain yield, revealed 6,068 polymorphic SNPs and 21 QTL regions showing homogeneity of contrasting alleles in the two bulks. The method was validated further with ‘CSR27/MI48’ RILs used earlier for mapping salt tolerance QTLs using low-density SSR markers. BSA with 50K SNP chip revealed 5,021 polymorphic loci and 34 QTL regions. This not only confirmed the location of previously mapped QTLs but also identified several new QTLs, and provided a rapid way to scan the whole genome for mapping QTLs for complex agronomic traits in rice.

The complete mitochondrial genome of the Anabas testudineus (Perciformes, Anabantidae) and its comparison with other related fish species

In the present study, the complete mitochondrial genome sequence of Anabas testudineusis reported using PGM sequencer (Ion Torrent, Life Technologies, La Jolla, CA). The complete mitogenome of climbing perch, A. testudineusis obtained by the de novo sequences assembly of genomic reads using the Torrent Mapping Alignment Program (TMAP), which is 16 603 bp in length. The mitogenome of A. testudineus composed of 13 protein- coding genes, two rRNA, and 22 tRNAs. Here, 20 tRNAs genes showed typical clover leaf model, and D-Loop as the control region along with gene order and organization, being closely similar to Osphronemidae and most of other Perciformes fish mitogenomes of NCBI databases. The mitogenome in the present study has 99% similarity to the complete mitogenome sequence of earlier reported A. testudineus. The phylogenetic analysis of Anabantidae depicted that their mitogenomes are closely related to each other. The complete mitogenome sequence of A. testudineus would be helpful in understanding the population genetics, phylogenetics, and evolution of Anabantidae.

Computational prediction of MHC class I epitopes for most common viral diseases in cattle (Bos taurus)

Viral diseases like foot-and-mouth disease (FMD), calf scour (CS), bovine viral diarrhea (BVD), infectious bovine rhinotracheitis (IBR) etc. affect the growth and milk production of cattle (Bos taurus) causing severe economic loss. Epitope-based vaccine designing have been evolved to provide a new strategy for therapeutic application of pathogen-specific immunity in animals. Therefore, identification of major histocompatibility complex (MHC) binding peptides as potential T-cell epitopes is widely applied in peptide vaccine designing and immunotherapy. In this study, MetaMHCI tool was used with seven different algorithms to predict the potential T-cell epitopes for FMD, BVD, IBR and CS in cattle. A total of 54 protein sequences were filtered out from a total set of 6351 sequences of the pathogens causing the said diseases using bioinformatics approaches. These selected protein sequences were used as the key inputs for MetaMHCI tool to predict the epitopes for the BoLA-All MHC class I allele of B. taurus. Further, the epitopes were ranked based on a proposed principal component analysis based epitope score (PbES). The best epitope for each disease based on its predictability through maximum number of predictors and low PbES was modeled in PEP-FOLD server and docked with the BoLA-A11 protein for understanding the MHC-epitope interaction. Finally, a total of 78 epitopes were predicted, out of which 27 were for FMD, 25 for BVD, 12 for CS and 14 for IBR. These epitopes could be artificially synthesized and recommended to vaccinate the cattle for the considered diseases. Besides, the methodology adapted here could also be used to predict and analyze the epitopes for other microbial diseases of important animal species.

Computational approaches, databases and tools for in silico motif discovery

Motifs are the biologically significant fragments of nucleotide or peptide sequences in a specific pattern. Motifs are categorized as structural motifs and sequence motifs. These are discovered by phylogenetic studies of similar genes across species. Structural motifs are formed by three dimensional arrangements of amino acids consisting of two or more α helices or β strands whereas sequence motifs are formed by the nucleotide fragments appearing in the exons of a gene. The arrangement of residues in structural motifs may not be continuous while it is continuous in sequence motifs. Sequence motifs may encode to the structural motifs. The algorithms used for motif discovery are important part of the bio-computational studies. The purpose of motif discovery is to identify patterns in biopolymer (nucleotide or protein) sequences to understand the structure and function of the molecules and their evolutionary aspects. The main aim of this paper is to provide systematic compilation of a review on different approaches, databases and tools used in motif discovery.

Extra-anatomical complications of antegrade double-J insertion

Introduction:

Insertion of a double-J (JJ) stent is a common procedure often carried out in the retrograde route by the urologists and the antegrade route by the radiologists. Reported complications include stent migration, encrustation, and fracture. Extra-anatomic placement of an antegrade JJ stent is a rare but infrequently recognized complication.

Materials and Methods:

We performed a retrospective audit of 165 antegrade JJ stent insertions performed over three consecutive years by a single interventional radiologist. All renal units were hydronephrotic at the time of nephrostomy. All procedures were performed under local anaesthetic with antibiotic prophylaxis.

Results:

Antegrade stent insertion was carried out simultaneously at the time of nephrostomy in 55 of the 165 cases (33%). The remainder were inserted at a mean of 2 weeks following decompression. In five (3%) patients, who had delayed antegrade stenting following nephrostomy, the procedure was complicated by silent ureteric perforation and an extra-anatomic placement of the stent. These complications had delayed manifestations, which included two retroperitoneal abscesses, a pelvic urinoma, a case each of ureterorectal fistula, and ureterovaginal fistula. Risk factors for ureteric perforation include previous pelvic malignancy, pelvic surgery, pelvic radiation, and a history of ureteric manipulation.

Conclusion:

Antegrade ureteric JJ stenting is a procedure not without complications. Extra-anatomic placement of the antegrade stent is a hitherto the infrequently reported complication but needs a high index of suspicion to be diagnosed. Risk factors for ureteric perforation at the time of stent insertion have to be considered to prevent this potential complication.

Extensive in silico analysis of NF1 splicing defects uncovers determinants for splicing outcome upon 5' splice-site disruption

We describe 94 pathogenic NF1 gene alterations in a cohort of 97 Austrian neurofibromatosis type 1 patients meeting the NIH criteria. All mutations were fully characterized at the genomic and mRNA levels. Over half of the patients carried novel mutations, and only a quarter carried recurrent minor-lesion mutations at 16 mutational warm spots. The remaining patients carried NF1 microdeletions (7%) and rare recurring mutations. Thirty-six of the mutations (38%) altered pre-mRNA splicing, and fall into five groups: exon skipping resulting from mutations at authentic splice sites (type I), cryptic exon inclusion caused by deep intronic mutations (type II), creation of de novo splice sites causing loss of exonic sequences (type III), activation of cryptic splice sites upon authentic splice-site disruption (type IV), and exonic sequence alterations causing exon skipping (type V). Extensive in silico analyses of 37 NF1 exons and surrounding intronic sequences suggested that the availability of a cryptic splice site combined with a strong natural upstream 3' splice site (3'ss)is the main determinant of cryptic splice-site activation upon 5' splice-site disruption. Furthermore, the exonic sequences downstream of exonic cryptic 5' splice sites (5'ss) resemble intronic more than exonic sequences with respect to exonic splicing enhancer and silencer density, helping to distinguish between exonic cryptic and pseudo 5'ss. This study provides valuable predictors for the splicing pathway used upon 5'ss mutation, and underscores the importance of using RNA-based techniques, together with methods to identify microdeletions and intragenic copy-number changes, for effective and reliable NF1 mutation detection.

Urethral metastasis: an uncommon presentation of a colonic adenocarcinoma

INTRODUCTION

Metastases to the urethra are a rare clinical entity. To our knowledge there are less than ten case reports described in the literature. In this report, however we describe a case of urethral metastases from a colonic cancer origin where the urethral lesion was the presenting symptom.

CASE REPORT

A 69-year-old woman presented with a swelling at the urethral opening. Per vaginal examination revealed a hard tender lesion situated at the external urethral meatus with contact bleeding. Excision biopsy revealed adenocarcinoma. Immunohistochemical staining demonstrated that the tumour cells were strongly suggestive of a metastatic lesion from the colon. Subsequent investigations revealed that the patient did indeed have a sigmoid adenocarcinoma and underwent chemotherapy with a view to anterior resection and pelvic exenteration.

DISCUSSION

Metastases to the urethra are rare. Treatment options have to be individualised to the extent of the disease and the symptoms of the patient. Immunohistochemical staining can help to a certain extent to point the direction towards the possible primary lesion. Atypical presentations of urethral lesions should be viewed with suspicion. A biopsy of the lesion is the only way of confirming diagnosis.

Chemopreventive effects of mustard (Brassica compestris) on chemically induced tumorigenesis in murine forestomach and uterine cervix

As there is a strong correlation between diet and cancer, the dietary constituents that inhibit mutagenesis and/or carcinogenesis are of paramount importance for the prevention of human cancer. In the present study, cancer chemopreventive potentials of different doses of mustard (Brassica compestris) seed mixed diets were evaluated against benzo(a)pyrene [B(a)P]-induced forestomach tumorigenesis and 3-methylcholantrene (MCA)-induced uterine cervix tumorigenesis. Results showed a significant inhibition of stomach tumour burden (tumours/ mouse) by mustard seeds. Tumour burden was 7.08 +/- 2.47 in the B(a)P-treated control group, whereas it was reduced to 1.36 +/- 1.12 (P<0.001) by the 2.5% dose and 1.18 +/- 0.87 (P<0.001) by the 5% dose of mustard seeds. The cervical carcinoma incidence, as compared to MCA-treated control group (73.33%), was reduced to nil (P<0.05) by the 5% diet of mustard seeds and to 13.33% (P<0.05) by the 7.5% diet of mustard seeds. The effect of the 2.5% and 5% mustard seed mixed diets was also examined on the antioxidant enzymes, glutathione content, lactate dehydrogenase (LDH) and lipid peroxidation in the liver of Swiss albino mice. The glutathione-S-transferase-specific activity was increased (P<0.05) by the 2.5% dose, whereas there was no significant change in the activity of DT-diaphorase. In antioxidant systems, significant elevation of the specific activities of superoxide dismutase and catalase was observed with both doses of mustard seeds (P<0.05). The level of reduced glutathione (GSH) measured as nonprotein sulphydryl content was elevated by the 2.5% dose of mustard seeds only (P<0.05). Lipid peroxidation measured as formation of thiobarbituric acid reactive substances production showed significant inhibition (P<0.05) by the 5% dose of mustard seed mixed diet. LDH activity was decreased significantly (P<0.05) by both the doses. The results strongly suggest the cancer chemopreventive potentials of mustard seeds and their ability to enhance the antioxidant defence system and in turn provide protection against the toxic effects of carcinogens. It is likely that the use of mustard seeds in the diet may contribute to reducing the risk of cancer incidence and burden in the human population.

Chronic renal insufficiency among Asian Indians with type 2 diabetes: I. Role of RAAS gene polymorphisms

Background

Renal failure in diabetes is mediated by multiple pathways. Experimental and clinical evidences suggest that renin-angiotensin-aldosterone system (RAAS) has a crucial role in diabetic kidney disease. A relationship between the RAAS genotypes and chronic renal insufficiency (CRI) among type 2 diabetes subjects has therefore been speculated. We investigated the contribution of selected RAAS gene polymorphisms to CRI among type 2 diabetic Asian Indian subjects.

Methods

Twelve single nucleotide polymorphisms (SNPs) from six genes namely-renin (REN), angiotensinogen (ATG), angiotensin converting enzyme I (ACE), angiotensin II type 1 receptor (AT1) and aldosterone synthase (CYP11B2) gene from the RAAS pathway and one from chymase pathway were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method and tested for their association with diabetic CRI using a case-control approach. Successive cases presenting to study centres with type 2 diabetes of ≥2 years duration and moderate CRI diagnosed by serum creatinine ≥3 mg/dl after exclusion of non-diabetic causes of CRI (n = 196) were compared with diabetes subjects with no evidence of renal disease (n = 225). Logistic regression analysis was carried out to correlate various clinical parameters with genotypes, and to study pair wise interactions between SNPs of different genes.

Results

Of the 12 SNPs genotyped, Glu53Stop in AGT and A>T (-777) in AT1 genes, were monomorphic and not included for further analysis. We observed a highly significant association of Met235Thr SNP in angiotensinogen gene with CRI (O.R. 2.68, 95%CI: 2.01–3.57 for Thr allele, O.R. 2.94, 95%CI: 1.88–4.59 for Thr/Thr genotype and O.R. 2.68, 95%CI: 1.97–3.64 for ACC haplotype). A significant allelic and genotypic association of T>C (-344) SNP in aldosterone synthase gene (O.R. 1.57, 95%CI: 1.16–2.14 and O.R. 1.81, 95%CI: 1.21–2.71 respectively), and genotypic association of GA genotype of G>A (-1903) in chymase gene (O.R. 2.06, 95%CI: 1.34–3.17) were also observed.

Conclusion

SNPs Met235Thr in angiotensinogen, T>C (-344) in aldosterone synthase, and G>A (-1903) in chymase genes are significantly associated with diabetic chronic renal insufficiency in Indian patients and warrant replication in larger sample sets. Use of such markers for prediction of susceptibility to diabetes specific renal disease in the ethnically Indian population appears promising.

Medical and surgical management of priapism

Priapism is a pathological condition of penile erection that persists beyond, or is unrelated to, sexual stimulation. Pathologically and clinically, two subtypes are seen-the high flow (non-ischaemic) variety and the low flow (ischaemic) priapism. The low flow type is more dangerous, as these patients are susceptible to greater complications and the long term recovery of erectile function is dependent on prompt and urgent intervention. Many of the causes of priapism are medical, including pharmacological agents, and as such, priapism should be considered as a medical and surgical emergency.

The ErbB-4 s80 intracellular domain is a constitutively active tyrosine kinase

The ErbB-4 receptor tyrosine kinase homo- and heterodimerizes following heregulin binding, which provokes increased levels of tyrosine autophosphorylation. Unique to the ErbB family, ErbB-4 is then proteolytically cleaved by alpha- and gamma-secretase to produce an 80 kDa intracellular domain (s80 ICD) fragment. This fragment is found in both the cytoplasm and nucleus of many normal and cancer cells and can interact with transcription factors in the cytoplasm and nucleus. Since the s80 ICD lacks ectodomain sequences known to play a major role in dimerization of ErbB family members, we asked whether the s80 ICD is an active tyrosine kinase. Here, we demonstrate that the s80 ICD is a constitutively active tyrosine kinase and can form homodimers. The s80 ICD is autophosphorylated in cells and can phosphorylate an exogenous substrate in vitro. Also, the s80 ICD can coassociate and dimers are detected by chemical crosslinking. This is the first example of constitutive kinase activation and dimerization totally within the cytoplasmic domain of an ErbB receptor and suggests that the s80 ICD may function to phosphorylate substrates in the cytoplasm or nucleus.

Tinospora cordifolia induces enzymes of carcinogen/drug metabolism and antioxidant system, and inhibits lipid peroxidation in mice

The present study is an effort to identify a potent chemopreventive agent against various diseases (including cancer) in which oxidative stress plays an important causative role. Here, we investigated the effect of a hydroalcoholic (80% ethanol: 20% distilled water) extract of aerial roots of Tinospora cordifolia (50 and 100mg/kg body wt./day for 2 weeks) on carcinogen/drug metabolizing phase-I and phase-II enzymes, antioxidant enzymes, glutathione (GSH) content, lactate dehydrogenase and lipid peroxidation in liver of 8-week-old Swiss albino mice. The modulatory effect of the extract was also examined on extrahepatic organs, i.e., lung, kidney and forestomach, for the activities of GSH S-transferase (GST), DT-diaphorase (DTD), superoxide dismutase (SOD) and catalase. Significant increases in the levels of acid-soluble sulfhydryl (-SH) and cytochrome P(450) contents, and enzyme activities of cytochrome P(450) reductase, cytochrome b(5) reductase, GST, DTD, SOD, catalase, GSH peroxidase (GPX) and GSH reductase (GR) were observed in the liver. Both treated groups showed decreased malondialdehyde (MDA) formation. In lung SOD, catalase and GST; in kidney SOD and catalase; and in forestomach SOD, DTD and GST showed significant increase at both dose levels of treatment. BHA (0.75%, w/w in diet), a pure antioxidant compound, was used as a positive control. This group showed increase in hepatic levels of GSH content, cytochrome b(5), DTD, GST, GR and catalase, whereas MDA formation was inhibited significantly. In the BHA-treated group, the lung and kidney showed increased levels of catalase, DTD and GST, whereas SOD was significantly increased in the kidney and forestomach; the latter also showed an increase in the activities of DTD and GST. The enhanced GSH level and enzyme activities involved in xenobiotic metabolism and maintaining antioxidant status of cells are suggestive of a chemopreventive efficacy of T. cordifolia against chemotoxicity, including carcinogenicity, which warrants further investigation of active principle (s) present in the extract responsible for the observed effects employing various carcinogenesis models.

Chemopreventive potential of Triphala (a composite Indian drug) on benzo(a)pyrene induced forestomach tumorigenesis in murine tumor model system

The present work is probably the first report on cancer chemopreventive potential of Triphala, a combination of fruit powder of three different plants namely Terminalia chebula, Terminalia belerica and Emblica officinalis. Triphala is a popular formulation of the Ayurvedic system of medicine. Our findings have shown that Triphala in diet has significantly reduced the benzo(a)pyrene [B(a)P] induced forestomach papillomagenesis in mice. In the short term treatment groups, the tumor incidences were lowered to 77.77% by both doses of Triphala mixed diet. In the case of long-term treatment the tumor incidences were reduced to 66.66% and 62.50% respectively by 2.5% and 5% triphala containing diet. Tumor burden was 7.27 +/- 1.16 in the B(a)P treated control group, whereas it reduced to 3.00 +/- 0.82 (p < 0.005) by 2.5% dose and 2.33 +/- 1.03 (p < 0.001) by 5% dose of Triphala. In long-term studies the tumor burden was reduced to 2.17 +/- 0.75 (p < 0.001) and 2.00 +/- 0.71 (p < 0.001) by 2.5% and 5% diet of Triphala, respectively. It was important to observe that Triphala was more effective in reducing tumor incidences compared to its individual constituents. Triphala also significantly increased the antioxidant status of animals which might have contributed to the chemoprevention. It was inferred that the concomitant use of multiple agents seemed to have a high degree of chemoprevention potential.

Oxidative stress in tumour-bearing fore-stomach and distant normal organs of Swiss albino mice

Antioxidant status in the tumour-bearing fore-stomach and distant normal organs (liver, spleen, kidney and heart) was investigated in Swiss albino mice. In addition, the cytochrome P450 (cyt P450) system was also examined in the liver. Benzo(a)pyrene [B(a)P] (8 doses of 1 mg/0.1 ml) was administered twice a week for 4 weeks to develop fore-stomach tumour. The animals were sacrificed at the end of 140 days. The specific activities of catalase (CAT), DT-diaphorase (DTD) and glutathione-S-transferase (GST) were found decreased, and the level of reduced glutathione (GSH) and the specific activity of lactate dehydrogenase (LDH) increased in the tumour-bearing fore-stomach; however, no change was observed in superoxide dismutase (SOD) activity. The specific activities of antioxidant enzymes, and levels of GSH were also altered in the normal organs, depending upon the type of tissue. In addition, the contents of cyt P450 and cyt b5, and the activity of NADPH cyt P450 reductase were significantly decreased in the liver. The results suggest increased oxidative stress in the tumour, and disturbance in the cooperative antioxidant functions in the distant normal organs. Inhibition of cyt P450 system reflected the possible adverse effect on drug metabolism function of the liver. Since, the antioxidant potential and the drug metabolism function were altered, the findings may have relevance to the radiation and chemotherapy of cancer.

Genetic susceptibility to tardive dyskinesia in chronic schizophrenia subjects: III. Lack of association of CYP3A4 and CYP2D6 gene polymorphisms

Tardive dyskinesia is a severe debilitating movement disorder characterized by choreoathetotic movements developing in one-fifth of the patients with schizophrenia. In this study we have investigated the significance of CYP3A4*1B and CYP2D6*4 polymorphisms in TD susceptibility among chronic schizophrenia patients (n = 335) from north India. Tardive dyskinesia was diagnosed in approximately 29% (96/335) of these patients. No significant association of either of the two SNPs with TD (CYP3A4*1B chi2 = 0. 308, df = 1, p = 0.579; CYP2D6*4 chi2 = 0.006, df = 1, p = 0.935) was observed. However a trend towards increased severity of TD in patients heterozygous for the CYP2D6*4 mutation was observed.

Detection of Pseudomonas aeruginosa type III antibodies in children with tracheostomies

Pseudomonas aeruginosa is often cultured from the airways of children with tracheostomies. P. aeruginosa produces exotoxin A (ETA) and type III cytotoxins. This study tested the hypothesis that children with tracheostomies are colonized by P. aeruginosa that express these virulence factors and will have antibodies directed against these virulence factors, indicating infection rather than only colonization. A convenience sample of 30 patients, ranging in age from 2 months-22 years, was recruited. Serum was tested for the presence of antibodies to ETA and components of the type III system by Western blot analysis. Twenty-one of 39 patients (70%) had antibodies to components of the type III system. Fifteen of 30 (50%) were seropositive for ETA. Sera from patients who were antibody-positive for ETA were also seropositive for either ExoS or ExoU. Nine of 30 patients (30%) did not possess antibodies to ETA or components of the type III system. In conclusion, these data identified a seropositive reaction to P. aeruginosa cytotoxins in some patients with tracheostomies, suggestive of infection by cytotoxic strains of P. aeruginosa. Future studies will determine the utility of measuring seroconversion to these cytotoxins as an early indication of infection in children with tracheostomies.

Genetic susceptibility to Tardive Dyskinesia in chronic schizophrenia subjects: I. Association of CYP1A2 gene polymorphism

Understanding the pharmacogenetic basis of developing iatrogenic disorders such as Tardive Dyskinesia (TD) has significant clinical implications. CYP1A2, an inducible gene of the cytochrome P450 family of genes, has been suggested to contribute to the metabolism of typical antipsychotics in subjects with schizophrenia on long-term treatment, and has been considered as a potential candidate gene for development of TD. In this study, we have investigated the significance of CYP1A2 gene polymorphisms in TD susceptibility among chronic schizophrenia sufferers (n=335) from north India. TD was diagnosed in approximately 29% (96/335) of these subjects. Of the 96 TD positives, 28 had been treated with typical antipsychotics alone, 23 with atypical antipsychotics alone and 45 patients had received both classes of drugs during the course of their illness. Out of the six SNPs tested, CYP1A2(*)2, (*)4, (*)5, (*)6 were found to be monomorphic in our population. CYP1A2(*)1C and CYP1A2(*)1F were polymorphic and were analyzed in the study sample. Since these two allelic variants lead to lesser inducibility among smokers, the smoking status of TD patients was also considered for all subsequent analysis. We observed increased severity of TD among TD-Y smokers, who were carriers of CYP1A2(*)1C (G>A) variant allele and had received only typical antipsychotic drugs (F(1,8)=9.203, P=0.016). No significant association of CYP1A2(*)1F with TD was observed irrespective of the class of drug they received or their smoking status. However, we found a significant association of CYP1A2(*)1F with schizophrenia (chi(2)=6.572, df=2, P=0.037).