In 2015 the first complete orchid genome sequence was published (doi:10.1038/ng.3149) and several others are on the way. The genome was for Phalaenopsis equestris but the main findings probably apply to most or all orchids. I won't talk about the results of this paper, which frankly, like most genome sequence papers these days, are a bit dull (although that is my professional area of work so they seem routine to me and would probably be highly technical and unreadable to you). What I will talk about instead is the astounding and ongoing drop in the cost of sequencing DNA and what it will mean for the future of ... drum roll please ... orchids. Not people! Who cares about people! Plus the promise of "personalized medicine" (roughly meaning medicine that takes into account your very own unique genome sequence) has been extensively written about and wildly over hyped in mainstream media. Here's what you can actually expect from personalized medicine: not much, or at least not for a very long time. Incremental improvements in a few cancer treatments and in judging appropriate drug dosages. That's it. Not even close to vaccines or antibiotics or good old segregation of sewage from drinking water.
Okay, now that I have offended most of the biomedical community, big pharma, little pharma, and half my readership, let's get down to things that matter: orchids. To do that I need to talk a bit about sequencing costs. Since DNA sequencing went large scale in the mid 1990s, the cost of determining the sequence of a segment of DNA has dropped by 4 or 5 orders of magnitude (factors of 10). This is a much faster gain than the famous Moore's Law for semiconductors on a chip. And the cost drop for now (2017) is continuing at about the same pace. It is likely that the cost of sequencing your (human) genome will be on the order of the cost of a postage stamp in a few years. (This is only the cost of running and amortizing the sequencing machine itself - at some point sample preparation, analysis of the output, and other ancillary activities will become more expensive than the sequencing itself.) Orchid genomes are substantially smaller than human genomes, so their cost will be proportionally smaller as well.
What does this mean for the hobby orchid grower? Well, mostly two things that I can think of at the moment. 1) All of that squabbling about taxonomic classification will be laid to rest (well, almost all of it). 2) No more need for misidentified plants, elaborate hybrid naming systems (and errors), and all of the aggravations that come with them. When you purchase a Dendrobium guerreroi 'CC9607' there will be no excuse for it being anything else. The frequency of these errors is high from what I can tell by reading responsible blogs from serious orchid growers. And the name Dendrobium guerreroi will stay Dendrobium guerreroi permanently. In theory, we can get rid of all these imprecise names altogether: you will simply say I have a "GCCTAGAATCGATC... [1 billion more letters]". Hmm, maybe that won't work.
If you are an orchid hybridizer, cheap DNA sequence could mean a lot more - being able to follow all the traits you care about through crosses without have to wait 10 years for a plant to mature. This won't be easy in the near term, but eventually the technology will assist in all kinds of directed breeding efforts, including make a hybrid Cattleya that is compact, grows fast, makes myriads of brilliantly colored flowers, tastes delicious, and whatever else you can track.
Though the cost of sequencing a genome will be very small, the machines and computers needed to get the sequence are still quite large and specialized, so for the time being you will generate sequence by sending samples to a center. A sample can be as small as snippet of leaf or root. There are handheld DNA sequencing machines available and/or on the near horizon but they are much more expensive per DNA sequence than the cheapest center-based technology. Nevertheless, we can probably expect a DNA sequencer in every, oh ... let's say library or corner store or something of that sort, in the near future. (Notice how I have cleverly used the vague term "near future" so that I can claim to be correct no matter what happens.) When will this all appear on your cell phone? Who knows, maybe never because it is too specialized, although it is possible I am not being imaginative enough. Not many people walk around thinking "I wonder whether the genome sequence of that dandelion is special in some way?". I do, but you probably don't. Unless you are odd and have a hobby like growing orchids.
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