I’m at an ICE pre-conference session organised by the USDA (Kevin Hackett) on “Pollinator gene banks”, especially focused on the honey bee (more about that later on).
A gene bank is a repository of different natural variaties and breeding lines of insects. This bank is preferably composed of cold live bees, cryopreserved whole tissue and sperm, or as diapaused individuals. The session started with an industry representative (Gene Brandi) explaining how important bee collection are to them, before moving on to USDA expert Joseph Rinehart who works mainly on the solitary bees. Jo explained how challenging it can be to store lines alive but also a number of tips to overcome these. A really cool trick was hypoxia (which I’ve been hearing about quite a bit these last year) as it can protect against oxydative stress. He also talked about preserving sperm but even more interesting was the cryopreservation of embryos: the community is making significant progress in a number of species including Medfly and screwworm (major SIT players) and the USDA team is expected to deliver exciting news next summer.
Washington U’s Steve Sheppard recaped on the phenotypic diversity captured within the honey bee subspecies including those that formed the USA’s honey bee industry. These subspecies had adapted at their native habitats (e.g. cold resistance). I wish someone could start characterising the genetic basis of these traits :-). In any case, America’s problem is that they can’t import Old World honey bees (disease risk) to enrich the “american” honeybee genetic stock. However they can import sperm! A second thing that would be interesting would be to see how – if at all – how honey bees from the USA, Australia and NZ actually differ: all have been introduced but have not only a vastly different importation history but also have survived very different climates.
Karen Kapheim from Utah State U opened her presentation with a cool concept: the “genomic iceberg” (actually a pyramid; I’m so going to use it!), at the very tip of the iceberg are common elements (think rDNA or repeats) and at the bottom are rarer genes. The genomic iceberg is important if you think of the two dimensions of the pyramid: the more common the elements are, the more you can use a reference genome; the rare elements which vary within species, you need new line-specific genomes. In between there is a range of different tools you could use (metabarcoding, “ultra-conserved elements” – I guess ribosomal proteins – enriched target capture, RAD variants, resequencing etc). Karen also briefly mentioned looking at the pollen in the bee guts: phenotyping them will allow us to understand the insect-plant interactions; this is something the HIE’s James Cook is just starting to do with Australian native bees so I hope we will have some robust protocols soon.
Shifting gears, Terry Griswold from the USDA at Logan brought up the obvious: how large and well maintained (and digitized) the American bee collections are (almost 700 species just in the west coast) and how they can assist further science. However, he did show that the sampling has been patchy with many sampling attempts having either too few individuals. Many were also not preserved for DNA (they have been collecting since 1880s!) and – a recurrent theme the last few years – the value and the deficit of curators.
Cory Sheffield (Canada’s Royal Saskatchewan Museum – and I thought my name was hard to pronounce) who works with Lawrence Parker, gave as the barcoder’s overview. There are now 20,139 described bees species (with USA, Brazil and Australia being hotspots); these are species described by systematicists and many but not enough (about 20-33%) have been barcoded. He gave a brief overview of how barcoding can assist with sexing, colour phenotyping and thus ultimately taxonomy.
The group then had a breakout and discussion but sadly I have to rush to mandatory duties, more tomorrow!