Unformatted text preview: us dominant.
homozygous Other Inheritance Patterns
Environment and the Phenotype
Pleiotropy Codominance ~ both alleles for a gene are fully
expressed, as opposed to one masking the
other. Incomplete dominance
phenotype of the heterozygote will be
intermediate between the phenotypes of the
Lethals Polygeneic Inheritance
Multiple genes converge to
result in a single
Each dominant allele is
additive to the overall
The more dominant alleles
a person has, the darker
the skin color
the genotype - genetic make-up
phenotype - observable traits
phenotype = genotype +environment Nature vs. Nurture
When one gene has more than one effect.
Mendel: seed coat color was always associated
with specific flower and axil colors.
Reflects the fact that most proteins have multiple
roles in distinct cell types
Any genetic change that alters gene expression
or function can potentially have wide-ranging
effects in a variety of tissues Pigmentation and Deafness in Cats
Approx. 40% of cats with white fur and blue eyes are
deaf (Hartl & Jones, 2005).
White cats with one blue eye and one yellow eye were
deaf only on the blue-eyed side.
The gene responsible affects pigmentation and the
ability to hear.
Possibly related to lack of ear canal fluid...
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This document was uploaded on 02/18/2014 for the course SOC 120 at Saint Louis University-Main Campus.
- Spring '13