Zusammenfassung der Ressource
Inheritance and
Pedigree Charts
- Co-Dominance
- both alleles are dominant and
expressed equally in the phenotype
- Example - ABO blood grouping, both alleles A and B
are Dominant and so are co-dominant,allele O is
recessive
- Incomplete Dominance
- One allele is dominant but not completely.
- the other allele will show in
the phenotype, but not to the
same extent.
- Example - Sickle Cell Anemia, HH
(normal), HsHs (sickle-cell anemia), HHs
(sickle cell trait - 30%)
- Sex - Linkage
- Genes attached to X chromosome are sex linked
genes as Y chromosome carries almost no genes.
- Conditions will
likely show in
the phenotype
of males
- Examples - Red/Green
colour blindness,
Haemophilia, Muscular
Dystrophy.
- Pedigree Charts
- Autosomal Dominant Inheritance.
- *Parents who are unaffected have
unaffected children. * the characteristic is
seen in every generation. *Both sexes are
equally affected.
- Autosomal Recessive Inheritance
- *Parents who are both heterozygous can have
affected children. *Children of affected parents
always inherit the recessive allele. *both sexes are
equally affected. * can skip generations
- Sex - linked Inheritance
- *Many more males then females are
affected. *only female can be carriers. *can
skip generations.