Chromosome number 2; that's where the weirdness came from

(this posting last altered Feb 11th 2009)
Apparently some UK researchers have made progress in identifying the genes for synaesthesia, and it looks like one synaesthesia gene could be associated with autism and epilepsy. This comes as no surprise to me. The identification of two cases of male-to-male transmission of synaesthesia appears to demolish the old theory that synaesthesia is transmitted genetically via the X-chromosome. The researchers found no evidence to support such a mode of transmission. Once again, I'm not surprised, as the body of evidence upon which this theory was based is suspect, as it was most likely an unreperesentative sample of the whole synaesthete population.

These UK synaesthesia researchers are now talking about a genetic test for synaesthesia. Why should such a thing be necessary, as any synaesthete who can talk should be able to disclose, if they wish, whether or not they have the condition? Well, the researchers like the idea of gene-based screening and early "diagnosis" of synaesthesia so that young children can be identified, so that bad things can be prevented from happening to them. The magazine stories about this study include suggestions that synaesthesia can interfere with learning to read. I've read a lot about synesthesia, but I don't recall reading any anecdote or study that supports such an assertion. My own experience of grapheme-colour synaesthesia suggests the opposite - that this condition is an aid to learing literacy rather than an impairment.
The story in New Scientist magazine is looks to me a bit like one of those mass media scare stories aimed at parents about autism screening and "early intervention". You know what I mean, don't you? - those stories that inevitably use those great journalistic autism-related cliches such as "red flags to look out for" and "alarms bells rang ...." Mercifully, these magazine articles about synaesthesia did not feature any flag-waving or pealing bells, but I believe they are still unecessarily alarmist. Would it be fair comment to say it's just the same old crap applied to another neurological condition?
New Scientist magazine web site article:
Robson, David (2009) Genetic roots of synaesthesia unearthed. New Scientist. February 5th 2009. http://www.newscientist.com/article/dn16537-genetic-roots-of-synaesthesia-unearthed.html
CNN web site article:
Landau, Elizabeth (2009) Seeing color in sounds has genetic link. CNN.com Febraury 9th 2009.
http://edition.cnn.com/2009/HEALTH/02/09/synesthesia.genes/index.html
The original research paper:
Julian E. Asher , Janine A. Lamb , Denise Brocklebank , Jean-Baptiste Cazier , Elena Maestrini , Laura Addis , Mallika Sen , Simon Baron-Cohen and Anthony P. Monaco (2009) A Whole-Genome Scan and Fine-Mapping Linkage Study of Auditory-Visual Synesthesia Reveals Evidence of Linkage to Chromosomes 2q24, 5q33, 6p12, and 12p12. American Journal of Human Genetics. February 5th 2009 (online publication).
Link to abstract:
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B8JDD-4VJ5CN5-8&_user=10&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=658bff91081ad9de702408b853031253