Discuss the genetics involved in the inheritance, Biology

Assignment Help:

Casein is the main protein in milk. There are three types of casein, one of which is beta casein. Beta casein comes in two main variants called A1 and A2. The order of amino acids in each variant is identical except for the 67th amino acid in the chain (see diagram below). In A1 beta casein, the 67th amino acid is histidine (His), while in A2 beta casein it is proline (Pro). Scientists believe that A2 was the original form of beta casein

Cows' milk that contains A1 beta casein is called A1 milk, while milk that contains A2 beta casein is called A2 milk. In New Zealand, 30% - 40% of dairy cows produce pure A2 milk. The rest produce either pure A1 milk or milk that is a mixture of both A1 and A2. From these figures, it can be calculated that the current frequency of the A1 allele is around 37%.

There are several breeds of dairy cow. Each breed has a combination of desirable characteristics that has been obtained through selective breeding. For example, the proportion of fat or protein in the milk, the amount of milk produced by the females, the breeding success of the females. Different breeds produce different types of milk in relation to beta casein. Some breeds produce mainly A1 milk, while other breeds produce mainly A2 milk. Recent research has suggested that there may be health benefits to humans in drinking A2 milk, as opposed to drinking A1 milk.

 

Discuss the genetics involved in the inheritance of the alleles responsible for the A1 and A2 casein  proteins in the milk of dairy cows. In your discussion, consider the following:

  • how the allele for A1 milk would have entered the gene pool
  • the pattern of inheritance shown by A1 and A2 milk
  • possible explanations for the current frequency of the A1 allele in the gene pool.

 


Related Discussions:- Discuss the genetics involved in the inheritance

Define biogeographic realm, Q. Define biogeographic realm? Biogeographi...

Q. Define biogeographic realm? Biogeographic regions are large areas that contain characteristic assemblages of animals and plants, d elineated on account of natural barriers s

Phylum, what is phulum cnideria

what is phulum cnideria

Homologous structures, Homologous structures are the body parts in differe...

Homologous structures are the body parts in different organisms which have similar bones and similar arrangements of the blood vessels, muscles, and nerves and go through similar

Ethylene production - responses to infection, Ethylene production - Res...

Ethylene production - Responses to Infection Ethylene is also induced in response to infection. It is also known to be produced under other stress conditions like wounding

What are the main causes of mutation, Q. What are the main causes of Mutati...

Q. What are the main causes of Mutation? Some mutations take place randomly and spontaneously during process of mitosis or meiosis. Others are caused by mutagenic agents that a

Where smooth muscle may be found in human body, a) Name three parts of the ...

a) Name three parts of the body where smooth (involuntary or unstriated) muscle may be found. b) In any one of your examples, say what the smooth muscle does.

Why is this area more vulnerable to damage than others, A small family was ...

A small family was traveling in the car when a minor accident happened. The children in the back seats were wearing lap belts, but still sustained numerous bruises about the abdome

Define mineral requirements during pregnancy period - iron, Define Mineral ...

Define Mineral Requirements during pregnancy period - Iron? While B 12 and folk acid are needed for the normal erythropoiesis, they must be accompanied by adequate amounts of

Surgical significance of inferior alveolar nerve and artery, Surgical signi...

Surgical significance of Inferior alveolar nerve and artery In an excessively resorbed ridge, the mental foramen with its contents of mental nerve and vessels, can be found o

Explanation of glomerular filtration, Question 1) Mentioning the 3 diff...

Question 1) Mentioning the 3 different processes in the formation of urine Explanation of Glomerular filtration Explanation of Tubular reabsorption Explanation of T

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd