Significant linkage disequilibrium between lhcgr1 and multiple LHB loci. In the schematic of LHB, exons are represented as black boxes and the positions of the 7 LHB polymorphisms scored are indicated by vertical lines. lhb3 is composed of two SNPs, which are in complete LD with each other. For each polymorphism, genotype frequencies are represented in the form of two pie charts, where the left chart represents genotype frequencies among individuals lacking an LQ-insert allele in exon 1 of LHCGR (lhcgr1) and the right chart represents genotype frequencies among individuals possessing 1 or 2 LQ-insert alleles. Frequencies above the graphs correspond to AD males, while frequencies below the graph correspond to all individuals sampled in this study. * = significant difference (p < 0.05), ** = highly significant difference (p < 0.01).