Sequencing and analysis of an Irish human genome

Background

Recent studies generating complete human sequences from Asian, African and European subgroups have revealed population-specific variation and disease susceptibility loci. Here, choosing a DNA sample from a population of interest due to its relative geographical isolation and genetic impact on further populations, we extend the above studies through the generation of 11-fold coverage of the first Irish human genome sequence.

Results

Using sequence data from a branch of the European ancestral tree as yet unsequenced, we identify variants that may be specific to this population. Through comparisons with HapMap and previous genetic association studies, we identified novel disease-associated variants, including a novel nonsense variant putatively associated with inflammatory bowel disease. We describe a novel method for improving SNP calling accuracy at low genome coverage using haplotype information. This analysis has implications for future re-sequencing studies and validates the imputation of Irish haplotypes using data from the current Human Genome Diversity Cell Line Panel (HGDP-CEPH). Finally, we identify gene duplication events as constituting significant targets of recent positive selection in the human lineage.

Conclusions

Our findings show that there remains utility in generating whole genome sequences to illustrate both general principles and reveal specific instances of human biology. With increasing access to low cost sequencing we would predict that even armed with the resources of a small research group a number of similar initiatives geared towards answering specific biological questions will emerge.     

Varietal Responses to Temperature in Swedes

Four swede varieties and their six F¹ hybrids were grown (for42 d) at different temperatures and also (for 32 d) under differentsoil and air temperature regimes. The weights of the F¹ hybridswere either intermediate to or resembled those of their parents.The varieties appeared to require a 10 °C difference betweenair and soil temperatures for optimal growth. The variety withthe lowest plant weight was Wilby and at low light intensityand under constant air and soil temperature this variety died.All varieties benefited by reduced soil or air temperature althoughthey varied in their optimal requirements. The results indicatedthat temperature x varietal interaction effects might have considerableimportance in the utilization of existing varieties or in thebreeding of new ones.     

Mechanism of Action of Luteinizing Hormone

WE have reported¹ studies on luteinized rat ovary in which we found that an approximate doubling of the rate of steroid synthesis following stimulation with luteinizing hormone was not associated with any change in the tissue NADPH/NADP⁺ concentration ratio. We concluded that it was unlikely that luteinizing hormone brought about the increase in steroid synthesis solely by increasing the production of NADPH by glucose 6-phosphate dehydrogenase or another cytoplasmic NADPH-linked dehydrogenase, as had been suggested^2,3.