Thomas Chair as Distinguished Professor in the Department of Anthropolgy, University of Utah

Cheap individual genotyping will give a new life to dating services and marriage arrangers. There is a market for sperm and egg donors today, but the information available to consumers about donors is limited. This industry will flourish as individual genotyping costs go down and knowledge of genomics grows.

Potential consumers will be able to evaluate not only whether or not a gamete provider has brown eyes, is tall or short, has a professional degree, but also whether the donor has the appropriate MHC genotypes, long or short androgen receptors, the desired dopamine receptor types, and so on. The list of criteria and the sophistication of algorithms matching consumers and donors will grow at an increasing rate in the next decade.

The idea of a "compatible couple" will have a whole new dimension. Consumers will have information about hundreds of relevant donor genetic polymorphisms to evaluate in the case of gamete markets. In marriage markets there will be evaluation by both parties. Where will all this lead? Three possibilities come immediately to mind:

A. Imagine that Sally is looking at the sperm donor market. Perhaps she is shopping for someone genetically compatible, for example with the right MHC types. She is a homozygote for the 7R allele of the DRD4 genetic locus so she is seeking a sperm donor homozygous for the 4R allele so she won't have to put up with a 7R homozygous child like she was. In other words whether Tom or Dick is a more desirable donor depends on characteristics specific to Sally.

B. But what if Sally values something like intelligence, which is almost completely unidimensional and of invariant polarity: nearly everyone values high intelligence. In this case Sally will evaluate Tom and Dick on simple scales that Sally shares with most other women, Tom will almost always be of higher value than Dick, and he will be able to obtain a higher price for his sperm.

C. Perhaps a new President has red-haired children. Suddenly Sally, along with most other women in the market, wants red-haired children because they are fashionable. Dick, with his red hair, is the sellout star of the sperm market but only for a short time. There is a cohort of children born with red hair, then the fad soon goes away as green eyes, say, become the new hot seller. Dick loses his status in the market and is forced to get a real job.

These three scenarios or any mix of them is a possible future for love and marriage among those prosperous enough to indulge in this market. Scenario A corresponds to traditional views of marriage: for everyone there is someone special and unique. Scenario B corresponds somewhat more closely to how marriage markets really work-every Sally prefers rich to poor, smart to dumb, and a BMW to a Yugo. Scenario C is close to one mechanism of what biologists call sexual selection: male mallards have green heads essentially because it is just the fashion. I would not wager much on which of these scenarios will dominate the coming gamete market but I favor scenario B.