A toolkit for rapid gene mapping in the nematode Caenorhabditis briggsae

<p>Abstract</p> <p>Background</p> <p>The nematode <it>C. briggsae </it>serves as a useful model organism for comparative analysis of developmental and behavioral processes. The amenability of <it>C. briggsae </it>to genetic manipulations and the availability of its genome sequence have prompted researchers to study evolutionary changes in gene function and signaling pathways. These studies rely on the availability of forward genetic tools such as mutants and mapping markers.</p> <p>Results</p> <p>We have computationally identified more than 30,000 polymorphisms (SNPs and indels) in <it>C. briggsae </it>strains AF16 and HK104. These include 1,363 SNPs that change restriction enzyme recognition sites (snip-SNPs) and 638 indels that range between 7 bp and 2 kb. We established bulk segregant and single animal-based PCR assay conditions and used these to test 107 polymorphisms. A total of 75 polymorphisms, consisting of 14 snip-SNPs and 61 indels, were experimentally confirmed with an overall success rate of 83%. The utility of polymorphisms in genetic studies was demonstrated by successful mapping of 12 mutations, including 5 that were localized to sub-chromosomal regions. Our mapping experiments have also revealed one case of a misassembled contig on chromosome 3.</p> <p>Conclusions</p> <p>We report a comprehensive set of polymorphisms in <it>C. briggsae </it>wild-type strains and demonstrate their use in mapping mutations. We also show that molecular markers can be useful tools to improve the <it>C. briggsae </it>genome sequence assembly. Our polymorphism resource promises to accelerate genetic and functional studies of <it>C. briggsae </it>genes.</p

Analysis of reproductive patterns of Sardinella longiceps (Valenciennes, 1847) from the Mumbai Sea, Maharashtra, India

In developing countries, management of fisheries resources is directly or indirectly dependent on fish reproductive biology &amp; conservation of the breeding grounds. Indian Oil Sardine fishery is a commercially important pelagic fishery along the coast of Mumbai. A Ganado-somatic index value of females was maximum (8.20) in September and minimum (0.38) in January. For males, the maximum Gonado-somatic index was 8.36 in September and the minimum 0.29 in February. Based on sex ratios month-wise, females were slightly more dominant in all months. There is a significant difference in the length-wise distribution of sexes, with a large number of females in higher length groups. Females attain the length at first maturity at 166.5 mm, and matured ovaries were seen in September and October, with a maximum percentage in September. It is estimated that the absolute fecundity ranged between 28,860 and 52,646, and the relative fecundity ranged between 450 and 684 number eggs per gram of fish weight

Analysis of reproductive patterns of Sardinella longiceps (Valenciennes, 1847) from the Mumbai Sea, Maharashtra, India

1037-1042In developing countries, management of fisheries resources is directly or indirectly dependent on fish reproductive biology & conservation of the breeding grounds. Indian Oil Sardine fishery is a commercially important pelagic fishery along the coast of Mumbai. A Ganado-somatic index value of females was maximum (8.20) in September and minimum (0.38) in January. For males, the maximum Gonado-somatic index was 8.36 in September and the minimum 0.29 in February. Based on sex ratios month-wise, females were slightly more dominant in all months. There is a significant difference in the length-wise distribution of sexes, with a large number of females in higher length groups. Females attain the length at first maturity at 166.5 mm, and matured ovaries were seen in September and October, with a maximum percentage in September. It is estimated that the absolute fecundity ranged between 28,860 and 52,646, and the relative fecundity ranged between 450 and 684 number eggs per gram of fish weight

A Toolkit for Rapid Gene Mapping in the Nematode \u3cem\u3eCaenorhabditis briggsae\u3c/em\u3e

Background The nematode C. briggsae serves as a useful model organism for comparative analysis of developmental and behavioral processes. The amenability of C. briggsae to genetic manipulations and the availability of its genome sequence have prompted researchers to study evolutionary changes in gene function and signaling pathways. These studies rely on the availability of forward genetic tools such as mutants and mapping markers. Results We have computationally identified more than 30,000 polymorphisms (SNPs and indels) in C. briggsae strains AF16 and HK104. These include 1,363 SNPs that change restriction enzyme recognition sites (snip-SNPs) and 638 indels that range between 7 bp and 2 kb. We established bulk segregant and single animal-based PCR assay conditions and used these to test 107 polymorphisms. A total of 75 polymorphisms, consisting of 14 snip-SNPs and 61 indels, were experimentally confirmed with an overall success rate of 83%. The utility of polymorphisms in genetic studies was demonstrated by successful mapping of 12 mutations, including 5 that were localized to sub-chromosomal regions. Our mapping experiments have also revealed one case of a misassembled contig on chromosome 3. Conclusions We report a comprehensive set of polymorphisms in C. briggsae wild-type strains and demonstrate their use in mapping mutations. We also show that molecular markers can be useful tools to improve the C. briggsae genome sequence assembly. Our polymorphism resource promises to accelerate genetic and functional studies of C. briggsae genes

ASSESS THE KNOWLEDGE AND ATTITUDE ON PREVENTION OF DENGUE AMONG THE PATIENTS ATTENDANTS

Objectives: Dengue infection is increasingly recognized as one of the worlds emerging infection disease. Lack of knowledge and unfavourable attitude regarding preventive measure of dengue among public is leading to outbreak of dengue in many parts of India. The aim of the study was to assess the level of knowledge and attitude on prevention of dengue among the patients attendants in Jawaharlal Institute of Postgraduate Medical Education and Research (JIPMER), Puducherry. Settings and Design: Descriptive cross-sectional study design. The study setting was Medical Record Department, JIPMER where patients came for the registration for the purpose of seeking treatment. Methods: The sample size was 176. The sampling technique used for the study was consecutive sampling who were satisfied with inclusion technique. The data collected with the help of questionnaire by face to face interview method. Statistical analysis used: All the categorical data were presented on frequencies, percentages, mean standard deviation, chi-square and correlation coefficient used to find the correlation of knowledge and attitude on dengue fever. Results: The study finding reported that 117(66.5%) of the participants had moderately adequate knowledge and 93 (52.8) moderately favorable attitude on prevention of dengue fever, at the same time adequate knowledge and most favorable attitude was not satisfactory level. Conclusions: It shows that public needs more educational intervention to improve their health practice against dengue by the health care provider

A Toolkit for Rapid Gene Mapping in the Nematode \u3cem\u3eCaenorhabditis briggsae\u3c/em\u3e

Background The nematode C. briggsae serves as a useful model organism for comparative analysis of developmental and behavioral processes. The amenability of C. briggsae to genetic manipulations and the availability of its genome sequence have prompted researchers to study evolutionary changes in gene function and signaling pathways. These studies rely on the availability of forward genetic tools such as mutants and mapping markers. Results We have computationally identified more than 30,000 polymorphisms (SNPs and indels) in C. briggsae strains AF16 and HK104. These include 1,363 SNPs that change restriction enzyme recognition sites (snip-SNPs) and 638 indels that range between 7 bp and 2 kb. We established bulk segregant and single animal-based PCR assay conditions and used these to test 107 polymorphisms. A total of 75 polymorphisms, consisting of 14 snip-SNPs and 61 indels, were experimentally confirmed with an overall success rate of 83%. The utility of polymorphisms in genetic studies was demonstrated by successful mapping of 12 mutations, including 5 that were localized to sub-chromosomal regions. Our mapping experiments have also revealed one case of a misassembled contig on chromosome 3. Conclusions We report a comprehensive set of polymorphisms in C. briggsae wild-type strains and demonstrate their use in mapping mutations. We also show that molecular markers can be useful tools to improve the C. briggsae genome sequence assembly. Our polymorphism resource promises to accelerate genetic and functional studies of C. briggsae genes