Chromosome 19 has the highest gene density of all human chromosomes, more than double the genome-wide average. The large clustered gene families, corresponding high G1C content, CpG islands and density of repetitive DNA indicate a chromosome rich in biological and evolutionary significance. Here we describe 55.8 million base pairs of highly accurate finished sequence representing 99.9% of the euchromatin portion of the chromosome. Manual curation of gene loci reveals 1,461 protein-coding genes and 321 pseudogenes. Among these are genes directly implicated in mendelian disorders, including familial hypercholesterolaemia and insulin-resistant diabetes. Nearly one-quarter of these genes belong to tandemly arranged families, encompassing more than 25% of the chromosome. Comparative analyses show a fascinating picture of conservation and divergence, revealing large blocks of gene orthology with rodents, scattered regions with more recent gene family expansions and deletions, and segments of coding and non-coding conservation with the distant fish species Takifugu.

No abstract

This article is a summary of conclusions derived from the 2006 analysis and report, “Reference Scenario – Systems Study of Priority Threat Contaminants in Water Venues,” published by the U.S. Department of Homeland Security, Science and Technology Directorate. The U.S. Environmental Protection Agency was a cooperating partner. The report chose three realistic terrorism scenarios for a detailed, end‐to‐end assessment of threat, vulnerability, and consequences. A qualitative selection process for determining relevant priority water contaminants included the following elements: physical characteristics (e.g., taste, odor, color), route of exposure (e.g., oral, dermal), toxicity, stability in water, and the availability of medical treatment. In the end, three venues were chosen and analyzed with one contaminant of concern.