This document discusses various hemoglobin derivatives that are formed due to ligands binding to the heme part of hemoglobin or changes in the iron oxidation state. It specifically describes carboxyhemoglobin which is formed when hemoglobin binds to carbon monoxide, preventing oxygen transport. Other derivatives discussed include methemoglobin and sulfhemoglobin. The document also examines hemoglobinopathies such as sickle cell anemia, caused by a single amino acid substitution, and thalassemias which involve impaired globin chain synthesis. Clinical manifestations and treatments for various hemoglobin derivatives and disorders are summarized.
Normal & abnormal hemoglobin derivativesrohini sane
Comprehensive presentation on Normal & abnormal hemoglobin derivatives for medical ,dental ,biotechnology & pharmacology students Comparison of molecular aspects & absorption spectra of normal & Meth-Hb are illustrated. Congenital & acquired Meth hemoglobinemia is described. briefly.Treatment of Meth-hemoglobinemia is presented along with its biochemical basis.Formation & clinical manifestations of Carboxy-hemoglobinemia is illustrated.Identification of Carboxy-hemoglobin in a diagnostic laboratory has been described for perusal of technologists.Google images are used to convey the aspect in a lucid way.
Normal & abnormal hemoglobin derivativesrohini sane
Comprehensive presentation on Normal & abnormal hemoglobin derivatives for medical ,dental ,biotechnology & pharmacology students Comparison of molecular aspects & absorption spectra of normal & Meth-Hb are illustrated. Congenital & acquired Meth hemoglobinemia is described. briefly.Treatment of Meth-hemoglobinemia is presented along with its biochemical basis.Formation & clinical manifestations of Carboxy-hemoglobinemia is illustrated.Identification of Carboxy-hemoglobin in a diagnostic laboratory has been described for perusal of technologists.Google images are used to convey the aspect in a lucid way.
billirubin production billirubin transport and metabolism, different laboratory methods of billirubin estimation ,normal and abnormal levels of billirubin, different classification and types of jaundice and liver diseses, liver functioning, enterohepatic circulation, billirubin production and degradation, benefits and diseases of abnormal level of billirubin
Electrophoresis of LDH Isoenzymes and Activity StainingASHIKH SEETHY
The slides prepared for MD(Biochemistry) and MSc (Biochemistry) teaching comprehensively covers isoenzymes, isoforms, clinical utility of Lactate Dehydrogenase (LDH), LDH isoenzymes and basics of zymography.
Download and view in presenter mode for better visual experience.
A comprehensive presentation on Hemoglobin chemistry for medical ,dental ,biotechnology ,Life sciences ,& pharmacology students. Presentation includes structure & functions of a normal hemoglobin molecule.Bohr's effect along with allosteric modulators of hemoglobin for oxygen transport are illustrated.Molecular changes ,types,diagnosis, Management & inheritance of Sickle cell anemia is described .Types , mutations involved ,diagnosis ,inhertance & Management of Thalassemia disease is presented here . Presentation also involves other hemoglobinopathies Hb C/D/E /Lepore/Wyane etc.Changes in oxygen carrying capacity of hemoglobin after formation of Carboxy Hemoglobin is illustrated . Formation of Meth-Hb in vivo & in vitro is described along with its genetic & diagnostic aspects.Unstable variants & chronic Heinz body anemia are described briefly .Text is supported by Google images.
challenges in interpreting abnormal hemoglobin study- the key is to correlate with patient age, ethnicity,RBC indices & morphology findings. Two tier approach for correct characterization of abnormal hemoglobins of HPLC &/or capillary electrophoresis.
billirubin production billirubin transport and metabolism, different laboratory methods of billirubin estimation ,normal and abnormal levels of billirubin, different classification and types of jaundice and liver diseses, liver functioning, enterohepatic circulation, billirubin production and degradation, benefits and diseases of abnormal level of billirubin
Electrophoresis of LDH Isoenzymes and Activity StainingASHIKH SEETHY
The slides prepared for MD(Biochemistry) and MSc (Biochemistry) teaching comprehensively covers isoenzymes, isoforms, clinical utility of Lactate Dehydrogenase (LDH), LDH isoenzymes and basics of zymography.
Download and view in presenter mode for better visual experience.
A comprehensive presentation on Hemoglobin chemistry for medical ,dental ,biotechnology ,Life sciences ,& pharmacology students. Presentation includes structure & functions of a normal hemoglobin molecule.Bohr's effect along with allosteric modulators of hemoglobin for oxygen transport are illustrated.Molecular changes ,types,diagnosis, Management & inheritance of Sickle cell anemia is described .Types , mutations involved ,diagnosis ,inhertance & Management of Thalassemia disease is presented here . Presentation also involves other hemoglobinopathies Hb C/D/E /Lepore/Wyane etc.Changes in oxygen carrying capacity of hemoglobin after formation of Carboxy Hemoglobin is illustrated . Formation of Meth-Hb in vivo & in vitro is described along with its genetic & diagnostic aspects.Unstable variants & chronic Heinz body anemia are described briefly .Text is supported by Google images.
challenges in interpreting abnormal hemoglobin study- the key is to correlate with patient age, ethnicity,RBC indices & morphology findings. Two tier approach for correct characterization of abnormal hemoglobins of HPLC &/or capillary electrophoresis.
describes the structure of hb, its variants in detail. Oxygen dissociation curve is explained with graph. Hemoglobinopathy is explained with diagram. myoglobin is also explained.
Daily bilirubin production - 250-300mg%
85% heme moiety of aged RBC
5% RBC precursors destroyed in bone marrow ( ineffective
erythropoiesis),Catabolism of some heme proteins – myoglobin,
cytochrome, peroxidase
Macromolecules of life (Nucleic acids & Proteins)Amany Elsayed
Macromolecules of life (Nucleic acids & Proteins)
The Fibrous Proteins
The Collagens
The Globular Proteins
Structure and Function of Myoglobin
Minor Hemoglobin’s
Biological value of proteins
Nitrogen Balance
Protein Deficiency
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
Lung Cancer: Artificial Intelligence, Synergetics, Complex System Analysis, S...Oleg Kshivets
RESULTS: Overall life span (LS) was 2252.1±1742.5 days and cumulative 5-year survival (5YS) reached 73.2%, 10 years – 64.8%, 20 years – 42.5%. 513 LCP lived more than 5 years (LS=3124.6±1525.6 days), 148 LCP – more than 10 years (LS=5054.4±1504.1 days).199 LCP died because of LC (LS=562.7±374.5 days). 5YS of LCP after bi/lobectomies was significantly superior in comparison with LCP after pneumonectomies (78.1% vs.63.7%, P=0.00001 by log-rank test). AT significantly improved 5YS (66.3% vs. 34.8%) (P=0.00000 by log-rank test) only for LCP with N1-2. Cox modeling displayed that 5YS of LCP significantly depended on: phase transition (PT) early-invasive LC in terms of synergetics, PT N0—N12, cell ratio factors (ratio between cancer cells- CC and blood cells subpopulations), G1-3, histology, glucose, AT, blood cell circuit, prothrombin index, heparin tolerance, recalcification time (P=0.000-0.038). Neural networks, genetic algorithm selection and bootstrap simulation revealed relationships between 5YS and PT early-invasive LC (rank=1), PT N0—N12 (rank=2), thrombocytes/CC (3), erythrocytes/CC (4), eosinophils/CC (5), healthy cells/CC (6), lymphocytes/CC (7), segmented neutrophils/CC (8), stick neutrophils/CC (9), monocytes/CC (10); leucocytes/CC (11). Correct prediction of 5YS was 100% by neural networks computing (area under ROC curve=1.0; error=0.0).
CONCLUSIONS: 5YS of LCP after radical procedures significantly depended on: 1) PT early-invasive cancer; 2) PT N0--N12; 3) cell ratio factors; 4) blood cell circuit; 5) biochemical factors; 6) hemostasis system; 7) AT; 8) LC characteristics; 9) LC cell dynamics; 10) surgery type: lobectomy/pneumonectomy; 11) anthropometric data. Optimal diagnosis and treatment strategies for LC are: 1) screening and early detection of LC; 2) availability of experienced thoracic surgeons because of complexity of radical procedures; 3) aggressive en block surgery and adequate lymph node dissection for completeness; 4) precise prediction; 5) adjuvant chemoimmunoradiotherapy for LCP with unfavorable prognosis.
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
2. • Hemoglobin derivatives are formed by the
combination of different ligands with the
heme part, or change in the oxidation state
of iron.
3. Carboxy-Hemoglobin (CO-Hb)
• Hemoglobin binds with carbon monoxide
(CO) to form carboxy-Hb.
• The affinity of CO to Hb is 200 times more than
that of oxygen.
• It is then unsuitable for oxygen transport.
4. • When one molecule of CO binds to one
monomer of the hemoglobin molecule, it
increases the affinity of others to O2; so that
the O2 bound to these monomers are not
released.
• This would further decrease the availability
of oxygen to the tissues.
5. Carbon Monoxide Poisoning
• CO is a colorless, odorless, tasteless gas
generated by incomplete combustion.
• CO poisoning is a major occupational hazard
for workers in mines.
• Breathing the automobile exhaust in closed
space is the commonest cause for CO
poisoning
6. • The carboxy-Hb level in normal people is
0.16%.
• An average smoker has an additional 4% of
CO-Hb.
• One cigarette liberates 10–20 ml carbon
monoxide into the lungs.
7. Clinical Manifestations
• Clinical symptoms manifest when carboxy-Hb
levels exceed 20%.
• Breathlessness, headache, nausea, vomiting,
& chest pain.
• At 40-60% saturation, death can result.
• Administration of O2 is the treatment.
8. Methemoglobin (Met-Hb)
• When the ferrous (Fe2+ ) iron is oxidized to
ferric (Fe3+) state, met-Hb is formed.
• Small quantities of met-Hb formed in the RBCs
are readily reduced back to the ferrous state
by met-Hb reductase enzyme systems.
• About 75% of the reducing activity is due to
enzyme system using NADH & cytochrome b5
9. Methemoglobinemias
• Normal blood has only less than 1% of
methemoglobin.
• It has markedly decreased capacity for
oxygen binding and transport.
• An increase in methemoglobin in blood,
(methemoglobinemia) is manifested as
cyanosis.
• Causes may be congenital or acquired.
10. Congenital Methemoglobinemia
• Presence of Hb variants like HbM can cause
congenital methemoglobinemia.
• Cytochrome b5 reductase deficiency is characterized
by cyanosis from birth.
• 10-15% of hemoglobin may exist as methemoglobin.
• Oral administration of methylene blue, 100-300
mg/day or ascorbic acid 200-500 mg/day decreases
met-Hb level to 5-10% and reverses the cyanosis.
11. Acquired or Toxic Methemoglobinemia
• Met-hemoglobinemia may develop by intake
of water containing nitrates or due to
absorption of aniline dyes.
• Drugs which produce met-hemoglobinemia -
acetaminophen, phenacetin, sulphanilamide,
amyl nitrite, & sodium nitroprusside.
12. Sulf-hemoglobinemia
• When hydrogen sulfide acts on oxy-Hb, sulf-hemoglobin
is produced.
• It occur in people taking drugs like
sulphonamides, phenacetin, acetanilide,
dapsone, etc.
• It cannot be converted back to oxy-hemoglobin.
13. Hemoglobinopathies
• Abnormal hemoglobins are the resultant of
mutations in the genes that code for α or β
chains of globin
• As many as 400 mutant hemoglobins are
known.
• About 95% of them are due to alteration in
single amino acid of globin
14. Types of abnormal Hb
• Two types:
• If the mutation affects structural gene, it
results in replacement of a single amino acid
in Hb by some other amino acid resulting into
abnormal Hb.
• E.g: Hb-S, Hb-M, Hb-C, Hb-D & others.
15. • If the mutation affects the regulator gene,
which affects the rate of synthesis of
peptide chains, the amino acid sequence
remains unaffected.
• E.g: Thalassaemias
16. Globin synthesis
• The globin genes are organised into two gene
families or clusters
• α-Gene family:
• There are 2 genes coding for α-globin chain
present on each one of chromosome 16.
• The ζ (zeta)-gene, other member of a-gene
cluster is also found on chromosome 16 & is
active during the embryonic development
17. • β-Gene family:
• The synthesis of β-globin occurs from a single
gene located on each one of chromosome 11.
• This chromosome also contains four other
genes.
• One ε-gene expressed in the early stages of
embryonic development.
18. • Two γ-genes (Gγ & Aγ) synthesize γ-globin
chains of fetal hemoglobin (HbF).
• One δ-gene producing δ-globin chain found in
adults to a minor extent (HbA2).
19. Sickle-cell anemia (HbS)
• Sickle-cell anemia (HbS) is the most common
form of abnormal hemoglobins.
• Erythrocytes of these patients adopt a sickle
shape (crescent like) at low oxygen
concentration
• It primarily occurs in the black population.
20. Molecular basis of HbS
• The glutamic acid in the 6th position of β chain
of HbA is changed to valine in HbS.
• This single amino acid substitution leads to
polymerization of hemoglobin molecules
inside RBCs.
• This causes a distortion of cell into sickle
shape
22. • The substitution of hydrophilic glutamic acid
by hydrophobic valine causes a localized
stickiness on the surface of the molecule
• The deoxygenated HbS may be depicted with
a protrusion on one side and a cavity on the
other side, so that many molecules can
adhere and polymerize
23. • The sickled cells form small plugs in
capillaries.
• Occlusion of major vessels can lead to
infarction in organs like spleen.
• Death usually occurs in the second decade of
life.
24. Homozygous and heterozygous HbS
• Sickle cell anemia is said to be homozygous, if
caused by inheritance of two mutant genes
(one from each parent) that code for β-chains.
• In case of heterozygous HbS, only one gene (of
β-chain) is affected while the other is normal
25. • The erythrocytes of heterozygotes contain
both HbS & HbA & the disease is referred to as
sickle cell trait.
• The individuals of sickle-cell trait lead a normal
life, & do not usually show clinical symptoms.
26. Abnormalities associated with HbS
• Life-long hemolytic anemia:
• The sickled erythrocytes are fragile & their
continuous breakdown leads to life-long
anemia.
• Tissue damage and pain:
• The sickled cells block the capillaries resulting
in poor blood supply to tissues.
• This leads to extensive damage & inflammation
of certain tissues causing pain.
27. • Increased susceptibility to infection :
• Hemolysis & tissue damage are accompanied
by increased susceptibility to infection &
diseases.
• Prematured eath:
• Homozygous individuals of sickle-cell anemia
die before they reach adulthood (< 20 years)
28. Mechanism of sickling in sickle-cell anemia
• Glutamate is a polar amino acid & it is
replaced by a non-polar valine in sickle-cell
hemoglobin.
• This causes a marked decrease in the solubility
of HbS in deoxygenated form
• Solubility of oxygenated HbS is unaffected
29. Sticky patches & formation of
deoxyhemoglobin fibres
• The substitution of valine for glutamate
results in a sticky patch on the outer surface
of β-chains.
• It is present on oxy- & deoxyhemoglobin S
but absent on HbA.
• There is a site or receptor complementary to
sticky patch on deoxyHbS.
30. • The sticky patch of one deoxyHbS binds with
the receptor of another deoxyHbS & this
process continuous resulting in the formation
of long aggregate molecules of deoxyHbS
• The polymerization of deoxy-HbS molecules
leads to long fibrous precipitates.
31. • These stiff fibres distort the erythrocytes into
a sickle or crescent shape
• The sickled erythrocytes are highly
vulnerable to lysis.
• ln case of oxyHbS, the complementary
receptor is masked, although the sticky patch
is present.
32. HbS gives protection against malaria
• HbS affords protection against Plasmodium
falciparum infection
• Hence the abnormal gene was found to offer
a biologic advantage.
34. Diagnosis of sickle cell anemia
• Sickling test:
• A simple microscopic examination of blood
smear prepared by adding reducing agents
such as sodium dithionite.
• Sickled erythrocytes can be detected under
the microscope
35. Electrophoresis
• Electrophoresis at alkaline pH shows a slower
moving band than HbA.
• At pH 8.6, carboxyl group of glutamic acid is
negatively charged.
• Lack of this charge on HbS makes it less negatively
charged, & decreases the electrophoretic mobility
• At acidic pH, HbS moves faster than HbA.
• In sickle cell trait, both the bands of HbA and HbS can
be noticed
37. Management of sickle cell disease
• Administration of sodium cyanate inhibits
sickling of erythrocytes
• Cyanate increases the affinity of O2 to HbS &
lowers the formation of deoxyHbS
• It causes certain side effects like peripheral
nerve damage
• In severe anemia, repeated blood transfusion
is required.
• It result in iron overload & cirrhosis of liver
38. Hemoglobin C disease
• Cooley's hemoglobinemia (HbC) is characterized by
substitution of glutamate by lysine in the sixth position
of β-chain.
• Due to the presence of lysine, HbC moves more slowly
on electrophoresis compared to HbA and HbS.
• HbC disease occurs only in blacks.
• Both homozygous & heterozygous individuals of HbC
disease are known.
• It is characterized by mild hemolytic anemia.
• No specific therapy is recommended.
39. Hemoglobin D
• Caused by the substitution of glutamine in
place of glutamate in the 121st position of β-
chain.
• Several variants of HbD are identified from
different places indicated by the suffix.
• For instance, HbD (Punjab)
• HbD, on electrophoresis moves along with
HbS.
40. Hemoglobin E
• Most common abnormal hemoglobin after HbS.
• lt is estimated that about 10% of the population in
South-East Asia (Bangladesh, Thailand, Myanmar)
suffer from HbE disease.
• In India, it is prevalent in West Bengal.
• HbE is characterized by replacement of glutamate by
lysine at 26th position of β-chain.
• The individuals of HbE (either homozygous or
heterozygous) have no clinical manifestations
41. Thalassemias
• Thalassemias are a group of hereditary
hemolytic disorders characterized by
impairment/imbalance in the synthesis of globin
chains of Hb
• Thalassemias (Greek: thalassa-sea) mostly
occur in the regions surrounding the
Mediterranean sea, hence the name.
• Also prevalent in Central Africa, India.
42. Molecular basis of thalassemias
• Hemoglobin contains 2α & 2β globin chains.
• The synthesis of individual chains is so
coordinated that each α-chain has a β-chain
partner & they combine to finally give
hemoglobin (α2β2).
• Thalassemias are characterized by a defect in
the production of α-or β-globin chain
43. • Thalassemias occur due to a variety of
molecular defects
• Gene deletion or substitution,
• Underproduction or instability of mRNA,
• Defect in the initiation of chain synthesis,
• Premature chain termination.
44. α-Thalassemiasas
• α-Thalassemias are caused by a decreased
synthesis or total absence of α-globin chain of
Hb.
• There are four copies of α-globin gene, two on
each one of the chromosome 16.
• Four types of α-thalassemias occur which
depend on the number of missing α-globin
genes
45. Salient features of different α -thalassemias
• Silent carrier state is due to loss of one of the
four α -globin genes with no physical
manifestations.
• α -Thalassemia trait caused by loss of two genes
(both from the same gene pair or one from each
gene pair).
• Minor anemia is observed
46. • Hemoglobin H disease, due to missing of three
genes, is associated with moderate anemia
• Hydrops fetalis is the most severe form of α-
thalassemias due to lack of all the four genes.
• The fetus usually survives until birth & then dies.
47. β-thalassemias
• Decreased synthesis or total lack of the
formation of β-globin chain causes β-
thalassemias.
• The production of α-globin chain continues to
be normal, leading to the formation of a globin
tetramer (α4) that precipitate.
• This causes premature death of erythrocytes.
• There are mainly two types of β-thalassemias
48. β-Thalassemia minor
• This is an heterozygous state with a defect in
only one of the two β-globin gene pairs on
chromosome 11.
• Also known as β -thalassemia trait, is usually
asymptomatic, since the individuals can make
some amount of β-globin from the affected
gene
49. β-Thalassemia major
• This is a homozygous state with a defect in
both the genes responsible for β-globin
synthesis.
• The infants born with β-thalassemia major
are healthy at birth since β-globin is not
synthesized during the fetal development
50. • They become severely anemic and die within
1-2 years.
• Frequent blood transfusion is required for
these children.
• This is associated with iron overload which in
turn may lead to death within 15-20 years
51. References
• Text book of Biochemistry – U Satyanarayana
• Text book of Biochemistry – DM Vasudevan
• Text book of Biochemistry – MN Chatterjea