Web search for dominant/recessive human traits, keeping in mind that most of our traits are not controlled by just one gene

Do a web search for dominant/recessive human traits, keeping in mind that most of our traits are not controlled by just one gene in a simple dominant/recessive manner.

Pick one trait that is controlled (mostly) by one gene in a dominant/recessive manner. This trait can either be one found in your family, or you can make up an example.

Answer the following questions about your chosen trait in the main response:

· What is your (or the made-up person's) phenotype for this trait?

· What is your (or the made-up person's) likely genotype for this trait? Note: there may be more than one possible genotype.

· What are the phenotypes and genotypes for the biological parents and possible siblings, or the other biological parent and biological children for this trait? (You need two generations for the Punnett Square)

· Create a likely Punnett Square for this trait in the described biological family (yours or the made-up example).

· Are there other factors that may determine the phenotype for this particular trait? Are more than one gene likely involved? Are other inheritance patterns involved? Is this trait impacted by environmental factors?

Full Answer Section

       
  • Possible siblings:
    • Could have detached earlobes (E_) or attached earlobes (ee)

Punnett Square:

E e
e Ee ee
e Ee ee
Genotypes:
    • Ee: Detached earlobes (carrier)
    • ee: Attached earlobes

Other Factors:

While attached earlobes are often used as a classic example of a single-gene trait, recent research suggests that multiple genes may be involved in determining earlobe shape. Additionally, environmental factors during development could potentially influence earlobe formation.

Sample Answer

       

Many human traits are influenced by multiple genes and environmental factors, but some exhibit a relatively simple dominant/recessive inheritance pattern. Let's explore one such trait:

Trait: Attached Earlobes

  • Phenotype: Attached earlobes (the earlobe is connected directly to the side of the head without a free lobe)
  • Likely Genotype: ee (homozygous recessive)

Family Example:

  • Made-up person: Sarah has attached earlobes.
  • Sarah's parents:
    • Mother: Detached earlobes (E_)
    • Father: Attached earlobes (ee)