I was reading the Wikipedia articles about genome-wide association studies (GWAS) and whole exome sequencing.
As I understand, GWAS is used to identify most common SNPs that are proved to be associated with a disease/disorder. On the other hand there is an article about whole exome sequencing method where it said that it is more sensitive to identify Mendelian mutations in contrast with the SNP genotyping methods used in GWAS.
As the graph shows below, there is a distinction between Mendelian mutations and common mutations. What exactly does Mendelian mutation mean (why do we call it Mendelian)? What makes a Mendelian mutation so rare but effective in contrast with common mutations? Aren't common mutations inherited with the same rules as Mendelian ones?