Location
Due to mutations on
Due to mutations in
Causing
in
Type
Type
therefore
due to
Leading To
Causing
and
Theory
Theory
Theory
Originated From
Due to
Location
Mutation of
type

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Other Affected Mammals

Mice

Gene Affected

HFE–/–

Phenotypes

Bottlenose Dolphins

Non Hereditary

Metabolic

Cattle

Hereditary (classic) Hemochromatosis

HFE Gene

Chromosome 6

Base Pair Substitution

r

Substitution of a change in the amino acids position from cysteine (C) to tyrosine (Y) as well as a histidine-to-aspartic acid substitution at amino acid position 63.

Most Commonly found in Humans

Europe & European Descendants

Ancient Bog people of Ireland

Sexual Selection

Endogamy in small communities
is prevalent

Improves chance of mating success

Common for preserve traditions and resources

Divergent Evolution

Rats, Horses, Dolphins and Humans are all mammals who descended from a common ancestor into new species

They all share the possibility of inheriting the HFE mutation or similar Phenotypes

Ecological Isolation

Genetic Drift

The Bog People live in an isolated environment

Founder Affect

Immigration of Celtic People from Northern Spain

Viking invasions

Great Change in Allele Frequency of New Population

Genetic Drift

Increase in the number of carriers of Hemochromatosis syndrome in the Bog People population

More carriers in a small endogamous population leading to a greater chance of children inheriting Hemochromatosis

Reason for increasing number of carriers

Increased fitness in Environment

Advancements in medicine & technology help people (including carriers) to live. Allowing carriers to reproduce with others risking the chance of mating with another carrier.

Irish Migrators/ Bog People create larger population numbers that are able to reproduce (middle aged)

Affects of Hemochromatosis only present later in life (around 50s)

Most Common in

How does Hemochromatosis still exist?

Autosomal Recessive Inheritance

Carriers of Hemochromatosis mutation are unaffected with no phenotypes of the disorder

Spontaneous Substitution Mutation ^

HFE gene

Both recessive alleles to be passed to children

Type 2 (Juvenile hemochromatosis)

HFE2 or HAMP genes

Type 3 (TFR2 Related)

Transferrin receptor 2 gene (TFR2)

Chromosome 7