Final answer:
Human genetics uses patterns of inheritance and molecular techniques to study how traits and diseases are transmitted. Pedigree analysis and genetic testing are vital tools in this field, which was initially based on Mendel's principles of inheritance.
Step-by-step explanation:
Human genetics is a field that focuses on the study of how traits and diseases are inherited in humans. Understanding the different patterns of inheritance, such as autosomal dominance, autosomal recessiveness, X-linked patterns, incomplete dominance, codominance, and lethality, allows geneticists to predict the likelihood of an individual inheriting a particular trait or disease. Analyses such as pedigree analysis and genetic testing, rather than test crosses which are unethical in humans, are commonly utilized to investigate these patterns.
Scientists use genetic inheritance to estimate the risk of disease transmission to offspring in cases of single-gene disorders, though multigenic diseases require consideration of environmental factors as well. Investigating human inheritance also includes studying mutations, which are changes in the nucleotide sequence of DNA that may lead to various phenotypes. Pioneering work by Gregor Mendel laid the foundation for these genetic principles, now expanded through modern technology such as genome sequencing.