Non-Mendelian

• Non-Mendelian


  Patterns of inheritance that do not follow Mendel's laws
• Non-Mendelian patterns of inheritance

  • Alleles are neither dominant nor recessive
  • Some traits have more than two contrasting alleles
  • Influenced by environmental and non-genetic factors
• Codominance


  When two dominant alleles are present, both alleles will be expressed when combined, resulting in a third phenotype in a heterozygous condition
• Incomplete Dominance


  When dominant alleles are absent, only a recessive allele will combine with another recessive allele
• Lethal Gene


  A condition when a certain combination of alleles will result in the death of the carrier
• Multiple Gene


  More than two alleles exist for a certain character
• Polygenic Inheritance


  One character is controlled by two or more genes
• Sex-linked Inheritance


  The inheritance of a trait determined by a gene located on one of the sex chromosomes
• Sex-Influenced Inheritance


  Autosomal traits whose expression of dominance is affected by the sex of the individual
• Pleiotropy


  A condition when one gene causes several effects (multiple traits) in various organs of the body
• Pedigree Analysis


  A chart that can represent a family tree along with the family members and their genetic traits