Ascaris Genome Sequencing

We aim to build comprehensive Ascaris genomic resources for the study of various aspects of parasitic nematode biology including developmental, chromosomal, and molecular biology. We initially sequenced Ascaris genome using DNA from mixed population of 32-64 cell embryos (~4.3X coverage of ABI 3730 and 454). Ascaris undergo an unusual DNA elimination process called chromatin diminution in early development when the germline is distinguished form the somatic cells. About 25% of the somatic genome is eliminated. We have sequenced ~13.7 X coverage (average 100 bp Illumina paired-end) of testis and intestine from a single male, an effort to determine sequences that are eliminated during diminution by comparing the somatic and germline genomes. We are planning to sequence additional spermatids and intestine DNA from a single male to achieve this aim. We have also generated a comprehensive transcriptome data set as well as small RNAs expressed during gametogenesis and embryogenesis to help annotate the genome.