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The Mexico City Prospective Study is a prospective cohort of more than 150,000 adults recruited two decades ago from the urban districts of Coyoacán and Iztapalapa in Mexico City1. Here we generated genotype and exome-sequencing data for all individuals and whole-genome sequencing data for 9,950 selected individuals. We describe high levels of relatedness and substantial heterogeneity in ancestry composition across individuals. Most sequenced individuals had admixed Indigenous American, European and African ancestry, with extensive admixture from Indigenous populations in central, southern and southeastern Mexico. Indigenous Mexican segments of the genome had lower levels of coding variation but an excess of homozygous loss-of-function variants compared with segments of African and European origin. We estimated ancestry-specific allele frequencies at 142 million genomic variants, with an effective sample size of 91,856 for Indigenous Mexican ancestry at exome variants, all available through a public browser. Using whole-genome sequencing, we developed an imputation reference panel that outperforms existing panels at common variants in individuals with high proportions of central, southern and southeastern Indigenous Mexican ancestry. Our work illustrates the value of genetic studies in diverse populations and provides foundational imputation and allele frequency resources for future genetic studies in Mexico and in the United States, where the Hispanic/Latino population is predominantly of Mexican descent.Genotype and exome sequencing of 150,000 participants and whole-genome sequencing of 9,950 selected individuals recruited into the Mexico City Prospective Study constitute a valuable, publicly available resource of non-European sequencing data. [ABSTRACT FROM AUTHOR]

Jim Baggott's Origins and Lisa Randall's Dark Matter and the Dinosaurs recount the greatest story ever told: the evolution of the Universe since the Big Bang. This rich cross-disciplinary tale [...]

The Grand Design: New Answers to the Ultimate Questions of Life STEPHEN HAWKING AND LEONARD MLODINOW Bantam Press: 2010. 208 pp. $28, 18.99 £ Despite publicity to the contrary, The [...]

Measurements of deuterium in high-redshift hydrogen clouds and of 3He in the local interstellar medium indicate that the 4He produced after the Big Bang constitute about 20% to 25% of all the elements by mass. The deuterium content gives important information about the nucleosynthesis and gives an estimate of baryon density. Nuclear reactions after the Big Bang caused the production of deuterium, 3He, 4He and 7Li.

Astrophysicist David Schramm was a graduate student at Caltech, where he worked with William A. Fowler and Gerald Wasserburg. He began his career investigating the origin of the heaviest elements in the explosions of stars, but his most significant work involved the production of the lightest elements in the Big Bang. He was particularly interested in deuterium, and used it to deduce the mass density of baryons present in the Universe. He was as enthusiastic about life as a whole as he was about science.