It can also be inferred by a decrease in linkage disequilibrium with increasing genetic map distance [7].
Our linkage disequilibrium analysis indicates declining inter-site linkage with increasing nucleotide distance within the Pvama1 sequences, in contrast to the significant linkage across the whole of the Pfama1 sequences (Figure 2).
The updated higher density linkage map improves QTL estimation and, along with a much denser SNP HapMap, greatly increases the likelihood of detecting SNPs in linkage with causal variants.
Genetic linkage analysis identified low level of neuroglobin expression in brain neurons with increased risk of Alzheimer's disease [ 7].
One approach to increase the power in linkage and association studies is to study small populations with increased linkage disequilibrium and decreased genetic diversity.
We find that Type I error increases gradually with increased linkage.
This notion is further supported by the results of recent MS linkage analyses; in these studies, with increasing power of the analysis, the HLA locus has gradually obtained higher LOD scores, eventually exceeding 11, while all other candidate loci have remained insignificant[18], [19].
In general, the linkage rate decreased with increasing age at diagnosis, and we thus performed analyses stratified by year of birth (all, birth year > 1930 and birth year > 1950).
A rare variant, the Gly180Ser mutation, was previously shown to increase in frequency with increasing BMI, providing further support for linkage between variants of the FFAR1 gene and BMI reported in the present study.
The saturation of SNP markers in our linkage map increased the resolution of QTL mapping.
