The number of pedigrees with linkage scan data was 158 and the number of individuals in those pedigrees with nicotine withdrawal sensitivity score data was 432. The autosome-wide MLS for the nicotine withdrawal sensitivity score linkage analysis was 3.15 at 164.5 cM on chr6q26 (Figure 2), with a multipoint P of 7×10−5 (Supplementary Table 1). A LOD score result of this magnitude was observed 37 times in 1000 simulated genome scans. The 1 and 2 LOD support intervals range from 152 to 172, and 147 to 178 cM, respectively. The average number of pedigrees and subjects with complete linkage scan genotype data and nicotine withdrawal sensitivity score data at the two markers flanking the MLS was 154 and 397, respectively. No other chromosomal regions with LOD scores > 2.0 other than chr6q26 were observed. Chromosomal regions with LOD scores > 1.0 were observed on chr1 at 112.1 cM (P=0.009), chr4 at 144.1 cM (P=0.0015), chr13 at 13.4 cM (P=0.004), and at chr15 at 74.8 cM (P=0.011), in addition to chr6q26 (see Supplementary Table 1 for a complete list of LOD Scores > 1 associated with the nicotine withdrawal sensitivity score).
