Non-Mendelian Inheritance

• Non-Mendelian Inheritance

  • pattern of inheritance which traits do not segregate in accordance with Mendel’s laws.
• Types of Non-Mendelian Inheritance:

  1. Incomplete Dominance
  2. Codominance
  3. Multiple Alleles
  4. Sex-Related Influence
  5. Sex-Influenced Traits
• Incomplete Dominance

  • one allele is partially dominant over another allele resulting in a blend or mixture of the two characteristics.
• Codominance

  • one allele is neither dominant over the other allele, resulting in the expression of both traits at the same time.
• Multiple Alleles

  • more than two alleles that control one gene.
  • ABO blood system
• ABO Blood System

  • O blood type is the universal donor (recessive)
  • AB blood type is the universal receiver.

  A) Positive

  B) Negative

  C) A

  D) B

  E) AB

  F) ii

  
• Sex Related Inheritance

  • Sex-Linked Traits
  • Located on the X and Y chromosomes.
  • can be seen in the chromosome 23
  • X-Linked Traits
  • refers to genetic conditions associated with mutations in genes on the X chromosome.
  • Ex = Color blindness, prostate cancer
  • Y-Linked Traits
  • Holandric Inheritance that is produced by genes located on Y chromosomes.
  • Can be difficult to detect. (Can be seen in the male).
• Sex-Influenced Traits

  • traits that may be expressed in both sexes but occur and are observed more frequently in one sex.
  • E.g. - Male pattern baldness