How can you use genetics to study human inheritance?

by analyzing how genes influence the development of phenotypic traits, i.e., by determining the association between phenotypic traits and changes in DNA sequence  

Explanation:

Genetics is a discipline that studies how genetic variation, i.e., the variation in the Deoxiriibunicleinc acid (DNA) molecule, is associated with the transmission of heredity, and how the environment influences this process. The DNA is a molecule that carries the instructions to perform all metabolic functions (eg., reproduction, development, growth, etc). Thus, advancements in genetics enabled us to decipher how phenotypic traits pass from parents/ancestors to their offspring/descendence. Genes are segments of DNA that carry the information (genetic information) to determine each phenotypic trait. During reproduction, genes are passed from one generation to the next, thereby transmitting this information across generations.