In the October issue of Nature Genetics, Siddique's team writes that
a mutated gene on chromosome 2 common to both families encodes a novel protein they dubbed alsin.
Not exact matches
When the researchers compared the mRNA to a library of DNA sequences taken from the dendrites of neurons by James Eberwine of the University of Pennsylvania Medical Center, they found that it came from a single
gene on chromosome X — the human version of which, when
mutated, leads to fragile - X syndrome.
When an X-linked
gene mutates in a woman, a backup
gene on the second X
chromosome can fill the gap.
But then a
gene on a single
chromosome mutated in a way that made any individual that inherited it male.
Now Cecilia Lai, Simon Fisher and colleagues, reporting in todays Nature, show that a
gene on chromosome 7, which they call FOXP2, is
mutated in the affected members of the KE family, as well as in an unrelated patient with a similar language deficit.
Using genetic maps, scientists know that the
mutated gene responsible for this tolerance lies
on chromosome 1, now they just need to find it.