That doesn't sound like a finding that, by itself, could be practically applied to the genetic screening of autistic people. I'm not too worried about that. Additionally, autism-related studies of this sort don't replicate a lot of times.
It seems to be a very difficult problem. Why is that? I'm sure different people have different views about this.
What I was wondering is whether experts dealing with a similarly elusive problem could provide some insights of note. The problem I'm referring to is that of finding the "race gene." The following are the recommendations regarding race and genetics by the National Human Genome Center of Howard University.
1. When the human species is viewed as a whole, underlying genetic variation and expressed physical traits exhibit gradients of differentiation, not discrete units. Therefore, modern extant humans do not fracture into races (subspecies) based on the modern phylogenetic criteria of molecular systematics.
2. The biological “boundaries” between any human divisions (groups, populations, nationalities) are circumstantial and largely dependent on what traits are chosen for emphasis.
3. The demographic units of human societies (and of the U.S. census) are the products of social or political rules, not the forces of biological evolution. The names and characteristics of demographic groups can change and have changed over time.
4. Group differences in health parameters are not encoded in the human genome as part of an evolutionary pattern of divergence. Thus, differences in health or disease cannot be treated as causally related to ethnoancestral groups.
5. Genotype-environment interactions are more important in explaining group differences in health than genotype, environment, or a factor called “race”.
6. The non-existence of human races (subspecies) does not mean the non-existence of racism. Racism is the structured systematic oppression against individuals and groups defined based on physical traits that reflect an extremely limited fraction of the human genome. Racism must be addressed.
7. Individuals cannot be treated as representative for all those who physically resemble them, or have some of the same ethnohistorical ancestry. Ancestries of individuals and groups should be ascertained in order to evaluate differential expression of genetic effects.
I thought that sounded quite pertinent.
I'm not saying that it won't ever be possible to fairly accurately distinguish an autistic person from a non-autistic one by simply looking at a genome sequence. As someone with a Computer Science background, I can theoretically speculate that someone will figure out a method eventually. I just don't think it will get done by simply looking for alleles that represent statistically significant "risk" factors.
See also: Race and Genetics at Wikipedia.