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Biology LibreTexts

8: Inheritance

  • Page ID
    16766
  • This chapter provides the molecular background for understanding heredity; explains Mendelian and non-Mendelian inheritance in humans; some genetic disorders and their treatment, and explores recent advances in genetics.

    • 8.1: Case Study: Genes and Inheritance
      People tend to look similar to their biological parents, as illustrated by the family tree above. But, you can also inherit traits from your parents that you can't see.
    • 8.2: Mendel's Experiments and Laws of Inheritance
      Mendel experimented with the inheritance of traits in pea plants at a time when the blending theory of inheritance was popular. This is the theory that offspring have a blend of the characteristics of their parents.
    • 8.3: Genetics of Inheritance
      Mendel did experiments with pea plants to show how traits such as seed shape and flower color are inherited. Based on his research, he developed his two well-known laws of inheritance: the law of segregation and the law of independent assortment.
    • 8.4: Mendelian Inheritance
      Mendelian inheritance refers to the inheritance of traits controlled by a single gene with two alleles, one of which may be completely dominant to the other. The pattern of inheritance of Mendelian traits depends on whether the traits are controlled by genes on autosomes or by genes on sex chromosomes.
    • 8.5: Non-Mendelian Inheritance
      Many human traits have more complicated modes of inheritance than Mendelian traits. Such modes of inheritance are called non-Mendelian inheritance, and they include inheritance of multiple allele traits, traits with codominance or incomplete dominance, and polygenic traits, among others.
    • 8.6: Genetic Disorders
      Genetic disorders are diseases, syndromes, or other abnormal conditions that are caused by mutations in one or more genes or by chromosomal alterations. Genetic disorders are typically present at birth, but they should not be confused with congenital disorders, which are any disorders, regardless of cause, that are present at birth. Some congenital disorders are not caused by genetic mutations or chromosomal alterations and are caused by problems during embryonic or fetal development.
    • 8.7: Case Study Cancer Conclusion and Chapter Summary
      Rebecca's family tree, as illustrated in the pedigree above, shows a high incidence of cancer among close relatives. But are genes the cause of cancer in this family? Only genetic testing, which is the sequencing of specific genes in an individual, can reveal whether a cancer-causing gene is being inherited in this family.