If a genetic counselor was examining a pedigree chart and noticed an occurrence of a disease in every generation, the counselor would most likely assume that the disease was caused by:

The pedigree chart shown depicts the inheritance pattern of __________.

Determine the likely pattern of inheritance in the following pedigree. List the genotypes of the numbered individuals in this order: #1, #2, and #3.

The following pedigree is for the ABO blood type group, which is an example of autosomal inheritance. Using the I^A, I^B, i for the alleles, fill in the top half of each box/circle with the genotype. Also, fill in the bottom half of each box/circle with the phenotype (A, B, AB, or O blood type). If it is impossible to know for certain a specific allele in the genotype, then place a '?' as a placeholder to represent the allele that is in question.