What is the alpha-globin gene family?
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What is the alpha-globin gene family?
In humans, the α-globin gene family resides on chromosome 16p13. 3 and is composed of a cluster of 3 genes (ζ2-α2-α1) with protein products that bind heme and assemble into hemoglobin.
How many copies of the alpha-globin gene are normally inherited?
two copies
Although there are typically two copies of α-globin, there can be variations in copy number, with greater than two copies in a single chromosome due to genetic recombination and unequal exchange of genetic material. In human adults, α-globin synthesis occurs in both copies of the α-globin gene at an α2:α1 ratio of 3:1.
What type of mutation is in the b globin gene?
In methemoglobinemia, beta-globin type, mutations in the HBB gene alter the beta-globin protein and promote the heme iron to change from ferrous to ferric. This altered hemoglobin gives the blood a brown color and causes a bluish appearance of the skin, lips, and nails (cyanosis).
What is HBB virus?
Hepatitis B is a vaccine-preventable liver infection caused by the hepatitis B virus (HBV). Hepatitis B is spread when blood, semen, or other body fluids from a person infected with the virus enters the body of someone who is not infected.
What does the alpha-globin gene do?
Alpha-globin is a component (subunit) of a larger protein called hemoglobin, which is the protein in red blood cells that carries oxygen to cells and tissues throughout the body. Hemoglobin is made up of four subunits: two subunits of alpha-globin and two subunits of another type of globin.
What is alpha-globin common mutation analysis?
Alpha-Globin Common Mutation Analysis – Alpha Thalassemia is a common hereditary trait and disease among individuals of Asian heritage. Disease ranges in severity from mild abnormalities of erythrocytic indices to severe anemia. Genetic counseling may be advised for some patients.
How mutations affect the beta-globin gene?
Mutations in globin genes cause thalassemias. Beta thalassemia affects one or both of the β-globin genes. These mutations result in the impaired synthesis of the β-globin protein portion, a component of Hb, thus causing anaemia.
What does HBB gene stand for?
Hemoglobin Subunit Beta
HBB (Hemoglobin Subunit Beta) is a Protein Coding gene. Diseases associated with HBB include Sickle Cell Anemia and Beta-Thalassemia, Dominant Inclusion Body Type.
Why hepatitis D is called delta hepatitis?
History. Hepatitis D virus was first reported in 1977 as a nuclear antigen in patients infected with HBV who had severe liver disease. This nuclear antigen was then thought to be a hepatitis B antigen and was called the delta antigen.
What does the HBS gene do?
Hb S results from the substitution of valine for glutamic acid at position 6 of the β globin chain. The resultant hemoglobin has reduced solubility at low oxygen tensions. Inheritance of one sickle globin gene leads to sickle trait whereas inheritance of two sickle globin genes leads to sickle cell anemia.
Is Alpha thalassemia a gene mutation?
Alpha thalassemia syndromes are caused by mutations on one or more of the four α-globin genes. Mutations could be either more commonly deletional or non-deletional. As some deletions (3.7 and 4.2) cause α+-thalassemia, some cause (-20.5, MED, THAI, FIL) α0 -thalassemia.
What is alpha thalassemia DNA analysis?
Preferred rst-tier genetic test for con rmation of suspected α thalassemia or α thalassemia trait Detects common, rare, and novel deletions or duplications in the α-globin gene cluster and its HS-40 regulatory region Multiplex ligation-dependent probe ampli cation (MLPA) used to detect Hb Constant Spring (HbCS) (HBA2 c …
What is the role of the alpha-globin gene?
Normal Function Alpha-globin is a component (subunit) of a larger protein called hemoglobin, which is the protein in red blood cells that carries oxygen to cells and tissues throughout the body.
Which β-globin gene mutation in human result in a structural hemoglobin defect?
β thalassemia is caused by a spectrum of mutations that results in a quantitative reduction of β globin chains that are structurally normal [3], in contrast to SCD which is caused by an abnormal Hb variant (HbS, βGlu6Val) that results from a point mutation in the HBB gene [4,5].
Why is hepatitis D is an unusual virus?
Hepatitis D infection cannot occur in the absence of hepatitis B virus. HDV-HBV co-infection is considered the most severe form of chronic viral hepatitis due to more rapid progression towards hepatocellular carcinoma and liver-related death. Vaccination against hepatitis B is the only method to prevent HDV infection.