Genetic linkage to chromosome 22q12 for a heavy-smoking quantitative trait in two independent samples.

We conducted a genomewide linkage screen of a simple heavy-smoking quantitative trait, the maximum number of cigarettes smoked in a 24-h period, using two independent samples: 289 Australian and 155 Finnish nuclear multiplex families, all of which were of European ancestry and were targeted for DNA analysis by use of probands with a heavy-smoking phenotype. We analyzed the trait, using a regression of identity-by-descent allele sharing on the sum and difference of the trait values for relative pairs. Suggestive linkage was detected on chromosome 22 at 27-29 cM in each sample, with a LOD score of 5.

Interconnections of CLN3, Hook1 and Rab proteins link Batten disease to defects in the endocytic pathway.

The endosomal/lysosomal transmembrane protein CLN3 is mutated in the Batten disease (juvenile neuronal ceroid lipofuscinosis, JNCL). However, the molecular mechanism of JNCL pathogenesis and the exact function of the CLN3 protein have remained unclear. Previous studies have shown that deletion of BTN1, the yeast orthologue of CLN3, leads to increased expression of BTN2.