Hemoglobin , derivatives and Structural / synthesis abnormalities

1. 4/10/2021
Dr.
V.P.Shah

2. WAY TO……
 RBC – in 1665 by Marcello Malpighi
 Isolation of Hb – in 1862 by Felix Hoppe
 Role of Hb for O2 transport – in 1904 by Christian Bohr
 Structure of Hb – in 1912 by Kuster
 Synthesized Hb in lab – in 1920 by Hans Fischer
 Three Dimensional stru. Of Hb – in 1962 by Perutz
4/10/2021
Dr.
V.P.Shah

3. SYNTHESIS OF HAEMOGLOBIN
4/10/2021
Dr.
V.P.Shah

4. HEMOGLOBIN
 Normal Level in blood:
Male : 14-16g/dl Female: 13-15g/dl
 HbA , HbA2, HbF
 HbA : 2 alpha and 2 beta chain – mole. Weight –
67,000 daltons (Normal level – 97%)
 HbF : 2 alpha and 2 gamma chains (normal level
1%)
 HbA2: 2 alpha and 2 delta chain (Normal level –
2%)
4/10/2021
Dr.
V.P.Shah

5. HEMOGLOBIN = HEME + GLOBIN
Heme:
 Derivatives of Porphyrins
 Porphyrins are cyclic compounds formed by fusion of 04
pyrrole ring linked by methenyl bridges
 Presence of Iron in Heme – Ferroprotoporphyrins
 Pyrrole rings are named as I,II, III, IV
 Bridges are named as alpha, Beta, Gamma & Delta
 Possible areas of substitution are 1-8
 Propionyl, Acetyl, Methyl and Vinyl
 The two hydrogen atoms in the –NH groups of pyrrole rings (II
and IV) are replaced by ferrous iron (Fe++)
 Occupy the centre of the compound ring structure
 Establish linkages with all the four nitrogens of all the pyrrole
rings.
4/10/2021
Dr.
V.P.Shah

6. 4/10/2021
Dr.
V.P.Shah

7. STRUCTURE OF HEMOGLOBIN
 Heme is located in a hydrophobic cleft of Globin
Chain
 04 Heme Residue per Hb Molecule
 Iron – Central Position of Porphyrin Ring –
Linked with pyrrole N by 04 cordinate valency
bond
 Reduced state – Fe++ -- Ferous Ion – 06 valency
(5th with imidazole N of Proximal Histidine) & (6th
valency Iron bind with O2 and formed Hydrogen
Bond with Imidazole N of Distal Histidine)
4/10/2021
Dr.
V.P.Shah

8. STRUCTURAL ORGANIZATION OF HB
 Primary structure:
 Globin subunit
 Secondary structure:
 Each globin chain contains several helical segments
separated by short non-helical segments
 8 helical segment in β,γ & δ chain designed as A, B, C,
D, E, F, G & H
 α chain lacks D segment & contains 7 helices
4/10/2021
Dr.
V.P.Shah

9. 4/10/2021
Dr.
V.P.Shah

10. 4/10/2021
Dr.
V.P.Shah

11.  Tertiary structure:
 Globin chain are highly compact structure
 Hydrophilic residues directed to exterior & hydrophobic
residues directed to interior
 Heme pocket
 Interaction of heme with globin by non-covalent
binding
 Quaternary structure:
 Tetramer of 4 polypeptide chain & 4 heme are held
together in definite arrangement or conformation by non-
covalent bonds such as hydrogen bond, ionic
interaction, hydrophobic interactions and van-der
waals forces to form quaternary structure.
4/10/2021
Dr.
V.P.Shah

12. 4/10/2021
Dr.
V.P.Shah

13. 4/10/2021
Dr.
V.P.Shah

14.  Hb A1
 Tetramer of 2 α subunit & 2 β subunit (α2β2)
 90-95 % major form of Hb
 Affinity of Hb A1 for O2 is lower than Hb F because of
high affinity of Hb A1 for 2,3 BPG
 Hb A2
 Tetramer of 2 α subunit & 2 δ subunit (α2δ2)
 Minor form 2%
4/10/2021
Dr.
V.P.Shah

15. FETAL HEMOGLOBIN (HBF)
 HbF has 2 Alpha chains and 2 Gamma Chains (having 146
Amino Acid)
 Increased Solubility of deoxy HbF
 Slower Electrophoretic Mobility of HbF
 Increased resistance of HbF to alkali denaturation
 HbF has decreased interaction with 2,3 BPG
 ODC of Fetus and Newborn are shifted to left.
 It helps in facilitating transplacental oxygen transport.
 HbF synthesis starts by 7th Week of gestation
 At birth 80% of Hb is HbF
 During first 06 months of life, it decreases to about 5% of
total
4/10/2021
Dr.
V.P.Shah

16. WHY HB F HAS HIGH AFFINITY FOR O2 THAN HB
A
 In γ chain one of the basic AA His-143 replaced by
neutral Serine AA
 This removes +ve charge from 2,3 BPG binding site
& reduces the affinity of fetal Hb for 2,3 BPG
 Thus ↑ ing the O2 binding affinity of fetal Hb relative
to that of maternal Hb.
4/10/2021
Dr.
V.P.Shah

17. 4/10/2021
Dr.
V.P.Shah

18. Globin synthesis, starts at 3rd week of gestation
 Embryonic
Haemoglobin Gower I ( z2e2)
Haemoglobin Portland ( z2g2)
Haemoglobin Gower II (a2e2)
 Fetal : HbF (a2g2), HbA (a2b2)
 Adult : HbA, HbA2 ( a2d2), HbF.
SYNTHESIS OF GLOBIN
4/10/2021
Dr.
V.P.Shah

19. 4/10/2021
Dr.
V.P.Shah

20. GLOBIN CHAIN SWITCH
4/10/2021
Dr.
V.P.Shah

21. GLYCOSYLATED HB (HBA1C)
 Aldehyde group of Glucose react with amino
group of N-terminal residue (Valine) of β chain in a
non-enzymatic reaction
 4 to 6 % of total Hb in blood
 Increased in DM
 Estimation of Glycosylated Hb useful for monitoring
long term control of hyperglycemia in DM patients
4/10/2021
Dr.
V.P.Shah

22. 4/10/2021
Dr.
V.P.Shah

23. TRANSPORT OF OXYGEN BY HEMOGLOBIN
 Ideal Respiratory Pigment:
 Transport Large Quantity of Oxygen
 Great Solubility
 Take up and release oxygen
 powerful buffer
4/10/2021
Dr.
V.P.Shah

24. TRANSPORT OF O2 FROM LUNGS TO TISSUES
 Oxygenation of Hb accompanied by
conformation changes in the tertiary &
quaternary structure of hb
 Conformational changes in Hb:
Widening of heme pockets
Movement of subunits
Movement of the iron atom
Disruption of salt bridge
4/10/2021
Dr.
V.P.Shah

25. 4/10/2021
Dr.
V.P.Shah

26. OXYGEN DISSOCIATION CURVE
 It helps in understanding of Hemoglobin ability to load
and unload oxygen at physiological pO2
 Sigmoid Shape of ODC is due to allosteric effect or
cooperativity
 Hill Equation expresses the equilibrium of Hb with
oxygen.
 Hb carries 20 ml of O2/dl (Hb level – 15 g/dl)
 pO2 values in : Inspired air 158 mm Hg
 Alveolar Air 100 mm Hg
 Blood in Lungs 90mm Hg (97% saturated)
 Capillary Bed 40 mm Hg (Hb saturation :60%)
4/10/2021
Dr.
V.P.Shah

27. 4/10/2021
Dr.
V.P.Shah

28. FACTORS AFFECTING OXYGEN DISSOCIATION
CURVE
 Heme-Heme Interaction and Cooperativity
 Positive Co operativity: Binding of Oxygen to one
Heme Residue increases affinity of remaining heme
residue for O2 (Homotropic Interaction)
 Heterotropic Interaction: Binding of 2,3-BPG
lowers affinity for O2
 Oxy Hb as R Form (Relaxed Form)
 De oxy Hb as T form (Tight Form)
 When Oxygenation occurs salt bonds are broken
down subsequently
 Hb – HbO2 – HbO4-HbO6-HbO8
4/10/2021
Dr.
V.P.Shah

29. 4/10/2021
Dr.
V.P.Shah

30. 4/10/2021
Dr.
V.P.Shah

31. THE BOHR EFFECT
 It is influence of pH and PCO2 to facilitate
oxygenation of Hb in lungs and deoxygenation
at the tissues
 In tissues:
 pCO2 elevated – pH falls – H+ concentration
increases (formation of Metabolic acids..
Lactate)
 O2 affinity will decreases – ODC shifted to
right- O2 released
 In Lungs:
 pCO2 low – pH high – pO2 significantly
elevated – O2 binds with Hb – ODC shifted
to left
4/10/2021
Dr.
V.P.Shah

32. 4/10/2021
Dr.
V.P.Shah

33. Effect of Temperature:
- p50 means Hb is half saturated with O2
- Elevation of temp from 20 to 37 C causes 88%
increase in p50
- Hypothermia – Metabolic Demand is low –
shift of ODC to left – less O2 to the tissues
- Febrile Condition – Increase needs of O2 –
Shift of ODC to right
4/10/2021
Dr.
V.P.Shah

34. THE CHLORIDE SHIFT – HAMBURGER EFFECT
4/10/2021
Dr.
V.P.Shah

35. 4/10/2021
Dr.
V.P.Shah

36. EFFECT OF 2,3-BPG
 Normal blood level- 15±1.5mg/g Hb
 Higher in Younger children
 It is intermediate of Glycolytic Pathway – Rapaport
Leubering Cycle/Shunt
 It binds with Deoxy Hemoglobin and stabilize T form
 During oxygenation 2,3 BPG released
 HbF contains gamma chain – having inability to bind
with 2,3 –BPG – So it has high affinity to O2
4/10/2021
Dr.
V.P.Shah

37. 4/10/2021
Dr.
V.P.Shah

38. 4/10/2021
Dr.
V.P.Shah

39. 4/10/2021
Dr.
V.P.Shah

40.  Right shift (easy oxygen delivery)
 High 2,3-BPG
 High H+
 High CO2
 HbS
 Left shift (give up oxygen less readily)
 Low 2,3-BPG
 HbF
HB-OXYGEN DISSOCIATION CURVE
4/10/2021
Dr.
V.P.Shah

41. HEMOGLOBIN – AS BUFFERING AGENT
 With the pH range of 7.0 to 7.8, most of the
physiological buffering action of Hb is due to the
“imidazole” group of amino acid “histidine”.
Imidazole contains two groups
1. Fe++ containing group which is concerned
with carriage of O2, and
2. Imidazole N2 group, which can give up H+
(proton) and accept H+ depending on the pH of the
medium.
Thus, buffering capacity of Hb is due to the
presence of “Imidazole” nitrogen group which
remains dissociated in acidic medium and
conjugate base forms.
4/10/2021
Dr.
V.P.Shah

42. DERIVATIVES OF HEMOGLOBIN
1. Action of Acids & Alkalis on Hb
4/10/2021
Dr.
V.P.Shah

43. DERIVATIVES OF HEMOGLOBIN
2. Haemin
 It is chemically haematin hydrochloride.
 Boiling oxy-Hb with NaCl and glacial acetic acid.
 Iron is oxidized in ferric form – bind with negatively
charged Cl- - to form hematin chloride
 Laboratory – blood are heated with Nippe’s Fluid –
forms dark brown rhombic crystals are seen
 Sensitive test – answered by heme part of blood of all
species
3. Haemochromogen
 Haem and the ferrous porphyrin complexes react
readily with basic substances such as hydrazines,
primary amines, pyridines, or an imidazole such as
the amino acid histidine, resulting compound is called a
haemochromogen (haemochrome)
4/10/2021
Dr.
V.P.Shah

44. 4. Haematoporphyrin
Mixing Blood with Sulphonic Acid
5. Haematoidin
Produced by the breakdown of Hb in the body.
Found as yellowish-red crystals in the region of old
blood extravasation.
6. Methaemoglobin
4/10/2021
Dr.
V.P.Shah

45. MET HEMOGLOBIN
 Ferous ion of Hb is oxidized to Ferric state – Met –
HB is formed ----- (Oxidized Stress- Generation of
Free Radicals)
 Prevented by : Met Hb reductase Enzyme
System – using NADH and Cytochrome b5
 Others – NADPH dependent System &
Glutathione Dependent Met – Hb reductase
Normal level – less than 1%
Congenital / Acquired Met hemoglobinemia
Cyanosis
4/10/2021
Dr.
V.P.Shah

46. METHEMOGLOBIN - CAUSES
 certain oxidant drugs or exposure to certain
poisons, e.g. chlorates, acetanilid, nitrites,
nitrobenzene, antipyrin, phenacetin, sulphonal, and
perhaps most important, the sulphonamide drugs.
 Use of Potassium Ferricyanide
 Nitrobenzene is used in manufacture of shoe
dyes,floor polishes, cosmetics and explosives.
 Fumes from carbon arcs contain nitrous oxide
Familial methaemoglobinaemia
 An inherited disorder due to lack or absence of
the enzyme methaemoglobin reductase,
4/10/2021
Dr.
V.P.Shah

47. MET – HB - SYMPTOMS
4/10/2021
Dr.
V.P.Shah

48. CONGENITAL MET HEMOGLOBINEMA
 Cytochrome b5 reductase deficiency
 Cynosis at birth
 Blood level – 10 -15%
 Treatment – Administration of Methylene Blue 100-
300 mg/day, Ascorbic Acid
4/10/2021
Dr.
V.P.Shah

49. MET-HB : TREATMENT
 Injection of intravenous glucose or methylene
blue, which helps to reduce Met-Hb (Fe+++) to Hb
(Fe++),
Methylene blue activates NADH or NADPH
dependant methaemoglobin reductase/
diaphorase I.
 Administration of ascorbic acid also helps in
reduction.
4/10/2021
Dr.
V.P.Shah

50. CARBOXY HEMOGLOBIN
 Hb binds with CO
 200 times more affinity for Hb
 Not suitable for O2 transport
 One mole. Bind with one monomer of Hb – increase
affinity of other monomer for o2
 O2 bind with this monomer can not release
 Decrease availability of O2 to tissues
4/10/2021
Dr.
V.P.Shah

51. CARBOXY HB
 CO – Colorless, Odorless, tasteless gas –
generated by incomplete combustion
 Specifically CO Poisoning is seen in Mine Workers
& Automobile Industries
 Normal Blood level – 0.16%
Clinical Manifestation:
Level exceeds 20%
Symptoms – Breathlessness, Nausea, Headache,
Vomiting, Chest pain
Treatment – O2 , Hyperbaric Oxygen
4/10/2021
Dr.
V.P.Shah

52. CARRIAGE AS CARBAMINO HEMOGLOBIN
- 15% CO2 is carried as Carbamino Hemoglobin
- CO2 bind with Hb as a Carbamino Complex
- R-NH2 + CO2 --- R-NH-COOH
4/10/2021
Dr.
V.P.Shah

53. SULF HEMOGLOBINEMIA
 Reactions of Oxy Hb with Hydrogen sulfide
 Causes: Sulfonamide, Phenacetin, acetanilide,
dapsone
 Causes Basophilic stippling of RBC
Nitric Oxide
NO – Hb bind with high affinity
Increase half life of NO
T – state bind with NO
Delivers NO to tissue capillaries
4/10/2021
Dr.
V.P.Shah

54. HCN & CYANIDE
 Cyanides resides -inhibits cytochrome oxidase
a3 of electron transport chain and stops cellular
respiration.
 Treatment ---
 Formation of Cyanmethemoglobin – Not Toxic –
Injection of Sodium Nitrite – Methemoglobin –
Binds with Cyanide – Cyanmethemoglobin – slowly
convert into Cyanate and Hb
 Use of Sodium Thiosulphate - Thiocyanate
4/10/2021
Dr.
V.P.Shah

55.  What is the importance of Spectroscopy in Clinical
Chemistry and Forensic Science?
 Methaemoglobin is not found in blood normally.
Why?
 Oral Administration of Methylene Blue Dye or
Ascorbic Acid reverses cyanosis in
Methaemoglobinemias. Why?
 Why Coal Mine workers are at risk at Carbon
Monoxide Poisoning?
4/10/2021
Dr.
V.P.Shah

56. HAEMOGLOBINOPATHIES
 Inherited disorders of hemoglobin synthesis
(thalassaemias) or structure (sickle cell disorders) that
are responsible for significant morbidity and mortality
 These disorders result in errors in oxygen-carrying
capacity of hemoglobin Diseases linked to genetic
predisposition
 Sickle cell and Thalassaemia are inherited disorders that
are passed on from parents to children through unusual
haemoglobin genes
4/10/2021
Dr.
V.P.Shah

57. 4/10/2021
Dr.
V.P.Shah

58. Presentation -:
 Disease: they inherit two unusual haemoglobin genes –
one from their mother, and one from their father.
 Trait/Carrier: People who inherit just one unusual gene
are known as ‘carriers’. (‘trait’.) Carriers are healthy and
do not have the disorders
4/10/2021
Dr.
V.P.Shah

59. 4/10/2021
Dr.
V.P.Shah

60. 4/10/2021
Dr.
V.P.Shah

61.  Quantitative Hemoglobinopathies:
lack or ↓ ed synthesis of either α or β globin chain,
altered combination of normal chain e.g.
Thalassemia
 Qualitative /Structural Hemoglobinopathies:
altered sequence of AAs, usually in one of the
constituent chains e.g. Sickle cell disease,
Hb C d’se, Hb M d’se
4/10/2021
Dr.
V.P.Shah

62. HEMOGLOBIN VARIANT CLASSIFICATION:
 Sickle Syndromes
Sickle cell trait (AS)
Sickle Cell Disease with SS, SC , SD, SO, varieties and S Beta
Thalassemia
 Unstable Hemoglobin:Congenital Heinz body Anemia, Hb Zurich,
Hb Kohn
 Hemoglobin with abnormal oxygen affinity
High Affinity : Polycythemia (Familial) , Hb Chesapeake, Hb Kansas
Low Affinity : Cyanosis (Familial) , HbM, Hb Rainier
 Structural Variations leading to Thalassemia
Alpha Thalassemia : Hb Constant Spring, Delta beta thalassemia,
Hb Lepore
Beta Thalassemia : Hb Quong sze
4/10/2021
Dr.
V.P.Shah

63. Sickle cell Hb (Hb S):
Abnormal Hb causes sickle cell anemia depending on
mode of inheritance
 Sickle cell anemia: results from homozygous inheritance
of Hb S gene (Hb SS)
 Homozygous : Contains 0 - 20% HbA and 80 -100% HbS
 Sickle cell trait: refers to the heterozygous inheritance of
Hb S gene (Hb AS)
 Heterozygous: Contains 60 -80% HbA and 20 -40% HbS
4/10/2021
Dr.
V.P.Shah

64. GENETICS
 Hb S caused by substitution of a Valine for
Glutamic acid residue as the 6th AA in β globin
chain
 Results from a point mutation in DNA due to
substitution of Thymine for Adenine
 Population affected: Africa, India, Middle East &
Southern Europe
4/10/2021
Dr.
V.P.Shah

65. Hb – S :
 Defect : α 2 β 2
A6Val(Glutamic Acid) – Suggest replacement of
Gluctamic Acid(2 carboxy polar residue) by Valine(Non polar
residue)
 Its Effect: Alters distribution of +ve & -ve charges on protein
surface.
Difference between HbA and HbS
 As HbA, HbS also contains Oxygenated and Deoxygenated
forms while in circulation.
 But Deoxygenated form of HbS is only 2 % soluble then
Deoxygenated HbA and 1 % soluble then own oxy form.
4/10/2021
Dr.
V.P.Shah

66. PATHOPHYSIOLOGY
 The biochemical basis for the structural alterations
of Hb S
 Formation of rigid erythrocytes
 Obstruction of small blood vessels by rigid
erythrocytes (sickle cell crisis)
 Hemolytic anemia
4/10/2021
Dr.
V.P.Shah

67. PATHOPHYSIOLOGY
β α
α β
β α
α β
β α
α β
β α
α β
Complimentary
Site
Sticky Patch
OXYGENATED
DEOXYGENATED
4/10/2021
Dr.
V.P.Shah

68. 4/10/2021
Dr.
V.P.Shah

69. During Deoxygenated state of HbS,
 Sticky patch bind to complimentary site on another
Deoxygenated HbS molecule and causes polymerization of
Deoxy HbS which forms
 long fibrous precipitates extends throught Red Blood
Cells –
 Causes distortion and lysis of RB Cell
4/10/2021
Dr.
V.P.Shah

70. 4/10/2021
Dr.
V.P.Shah

71. CLINICAL FEATURES
 Chronic hemolytic anemia
 Vaso-occlusive crisis
 Sickle cell trait show increased resistance to
malaria specifically for plasmodium malaria
4/10/2021
Dr.
V.P.Shah

72. 4/10/2021
Dr.
V.P.Shah

73. FACTORS AFFECTING SEVERITY OF SICKLING
 ↓ O2 tension caused by high altitude
 ↑ CO2 concentration
 ↓ pH
 ↑ concentration of 2,3 BPG in RBC
 Hypoxia, Infections, Dehydration, Cold & acidosis
4/10/2021
Dr.
V.P.Shah

74. DIAGNOSIS
 Microcytic Hypochromic anemia: Hb ↓ (6-8 gm/dl)
 ↑ Reticulocyte count
 Sickling of red cell seen in microscope
 Sickle cell solubility test: reducing agent such as
sodium dithionate/ sodium metabisulfite
 Hb electrophoresis presence of Hb S
 Molecular Diagnosis: RFLP
4/10/2021
Dr.
V.P.Shah

75. HB ELECTROPHORESIS
4/10/2021
Dr.
V.P.Shah

76. MANAGEMENT
 Symptomatic Mx
 Hydroxyurea: antisickling drug interfere with normal
erythropoiesis in such a way to ↑ production of γ
chains leading to ↑ synthesis of Hb F (interfere with
sickling)
 Bone marrow transplantation
4/10/2021
Dr.
V.P.Shah

77.  The efficacy of hydroxyurea in the treatment of
sickle cell disease is generally attributed to its
ability to boost the levels of fetal hemoglobin
(Hb F,α2γ2).
 This lowers the concentration of Hb S within a cell
resulting in less polymerization of the abnormal
hemoglobin.
4/10/2021
Dr.
V.P.Shah

78. MAY BE DUE TO………
 HYDROXYUREA is cytotoxic to the more rapidly
dividing late erythroid precursors, an effect that
leads to the recruitment of early erythroid
precursors with an increased capacity to
produce Hb F.
 interrupt the transcription factors that selectively
bind to promoter or enhancer regions around the
globin genes, thereby altering the ratio of Hb A to
Hb F
 nitric oxide-derived mechanism for Hb F induction
 increases Hb F production by inhibiting
ribonucleotide.
4/10/2021
Dr.
V.P.Shah

79.  Imp:
 Resistant to Malaria in patients with Sickle cell ds.
- Malaria parasite spends a part of its life cycle in
erythrocyte – In HbS interrupts the parasite cycle
- MP increases the acidity – increase sickling of
Erythrocytes to 40%
- Concentration of K is low in sickled cells –
unfavorable for MP to survive.
 Increase incidence of Salmonella
4/10/2021
Dr.
V.P.Shah

80. Thalassem
ia
4/10/2021
Dr.
V.P.Shah

81. Group of genetically transmitted
disorders of Hb synthesis
characterized by Impairment /
Imbalance in syn. Of Globin chain
Thalasa means sea
Classified based on globin chain or
inheritance patterns
4/10/2021
Dr.
V.P.Shah

82. 4/10/2021
Dr.
V.P.Shah

83. BETA THALASSEMIA
 Structurally normal but defective
synthesis/production of beta globin chain of Hb
 Types: major & minor
 Excess of alpha chain to form α4 precipitate rapidly
within the RBC as heinz bodies, cell rupture &
death
 ↑ con. of Hb F & Hb A2
4/10/2021
Dr.
V.P.Shah

84. CAUSES
 Mutation of β globin chain (frame shift/ non-sense
mutations)
 Defective transcription due to mutation in
promoter or enhancer region
 Defective RNA processing due to defective
splicing
 Defective translation due to base exchange
mutation
 Frame shift mutation
4/10/2021
Dr.
V.P.Shah

85. THALASSEMIA MAJOR
Genetics: absence of both β globin
genes, homozygous state
 Age of onset & sex: early life (6th month of
age), affect both sex equally
 Geographical prevalence: mediterranean
region like south africa, india& south east
asia
 2-15% incidence
4/10/2021
Dr.
V.P.Shah

86. CLINICAL FEATURES
Hemolytic anemia (cooley’s anemia)
Splenomegaly
Hepatomegaly
4/10/2021
Dr.
V.P.Shah

87. COOLEY’S ANEMIA
Severe anemia of Infancy or early
childhood
Features – Mongoloid Features having
stunted growth, pallor, Icterus,
Splenomegaly
Hypochromic Microcytic Anemia
Blood Smear – Basophilic Strippling (a
blood smear in which erythrocytes
display small dots at the periphery.
These dots are the visualization of
ribosomes , Target Cell ++
4/10/2021
Dr.
V.P.Shah

88.  Skull Bone – Hair on end experience –
Radiographic appearance on a skull which
results from a periosteal reaction
manifesting as perpendicular trabeculations
interspersed radiolucent marrow
hyperplasia
4/10/2021
Dr.
V.P.Shah

89. DIAGNOSIS
 Microcytic hypochromic anemia
 ↓ Hb level (<7gm/dl)
 Reticulocytosis
 Fragmentation of erythrocytes
 Presence of inclusion bodies
 Serum iron ↑
 Serum ferritin ↑
4/10/2021
Dr.
V.P.Shah

90.  Hb electrophoresis:
 absence of Hb A (α2β2)
 ↑ Hb A2 (α2δ2)
 ↑ Hb F (α2γ2)
 Hair on end appearance in skull in X-ray
 Prenatal diag. chorionic or amniotic fluid sampling
4/10/2021
Dr.
V.P.Shah

91. TREATMENT
 Blood transfusion
 Folic acid supplements
 Iron chelation therapy (Desferrioxamine)
 Bone marrow transplantation (useful in young HLA
matched siblings)
4/10/2021
Dr.
V.P.Shah

92. THALASSEMIA MINOR
 Genetics: caused by the absence of only one
globin chain of Hb & heterozygous
 Benign condition, mild anemia
 Hb A +nt
 Hb A2 ↑
4/10/2021
Dr.
V.P.Shah

93. THALASSEMIA INTERMEDIA
 Caused by either combination of homozygous mild
β thalassemia & α thalassemia
 Β thalassemia & hereditary persistance of Hb or Hb
lepore (caused by defect DNA recombination of δ &
β chain of Hb)
 Moderate degree anemia, splenomegaly & gall
stone
 ↑ Hb F
4/10/2021
Dr.
V.P.Shah

94. Α-THALASSEMIA
 Are disorder of Hb synthesis caused by defective
syn. of α globin chain
 Resulting excess β & γ globin chain
 ↓ Hb A1, Hb A2, Hb F
 Causes: point mutation, insertion & deletion
4/10/2021
Dr.
V.P.Shah

95. 4/10/2021
Dr.
V.P.Shah

96. Silent thalassemia: one globin chain
absent,no clinical effect
α thalassemia trait: two globin chain
absent, benign condition
α thalassemia minor (Hb H d’se): three
globin chain absent, β4 accumulation
called Hb H, mild anemia
α thalassemia major (Hb Bart’s):four globin
chain absent, γ4 accumulation called Hb
bart, also called hydrops fetalis
4/10/2021
Dr.
V.P.Shah

97. HB C
 Replacement of 6 position of beta chain Glutamic
Acid by lysine
 More common on black race
 AC heterozygotes do not show any clinical
manifestations
4/10/2021
Dr.
V.P.Shah

98. HB E
 It is second most common hemoglobin variant
 Replacement of beta 26 glutamate by lysine
 More prevalent in west Bengals in India
4/10/2021
Dr.
V.P.Shah

99. HB D
 Replacement of beta 121 glutamate by glutamine
(HbD Punjab)
 HbSD disease is a severe condition
4/10/2021
Dr.
V.P.Shah

100. HB SABINE
 Defect : α2 A β2
91 Proline
 Substitution of β chain of Proline for
leucine at 91, this makes possible for
formation of methaemoglobin.
 Globin moiety not attached to Heme gets
precipitated in the erythrocyte – Inclusion
Bodies: attached to Cell Membrane –
Osmotic Damage causing hemolysis.
4/10/2021
Dr.
V.P.Shah

101. HB CHESAPEAKE
 Defect: α292Arg(Lysine) β2 A
 High affinity to oxygen – decreased release to
tissue causing tissue hypoxia – compensatory
Polycythemia
4/10/2021
Dr.
V.P.Shah

102. HB RAINIER
 Tyrosine replaced by Histidine at 145causing
stabilize R form and increase O2 Affinity
 Abnormal Hb which interferes with m –RNA
formation (Structural Variants)
4/10/2021
Dr.
V.P.Shah

103. HB CONSTANT SPRING
 Produce unstable m –RNA,
 UAA stop codon has mutated CAA which codes for
Glutamine hence α chain are 31 residues longer
than usual.
 The longer m –RNA (i.e 172 a.a) is unstable and
gets degraded readily.
4/10/2021
Dr.
V.P.Shah

104. QUESTIONS
 Describe the structure & function of Hb
 Describe the disorder of Hb
 Describe the causes, features & diagnosis of sickle
cell disease
 Describe the causes, features & diagnosis of beta
thalassemia
 Mention five disorders characterized by altered Hb
structure & function. Mention the underlying defect
& major clinical features of each condition
4/10/2021
Dr.
V.P.Shah

105. QUESTIONS
 What are causes of MetHb? Mention the effect of
MetHb on oxygenation of Hb. How it is detected.
List of two compounds used in treatment
 Mention different types of Hb their composition &
significance
 Describe ODC of Hb & mention the factors causing
shift of ODC
 Describe changes occuring during CO2 transport
4/10/2021
Dr.
V.P.Shah

106. QUESTIONS
 What are tactoid cells how they are formed mention
their significance
 Describe different form of alpha thal. & defect in
each type.
 Abnormal Hb
 Role of 2,3 BPG in transport of O2 by Hb
 MetHb
 Give differentiation point for T & R form of Hb
 Hb S
4/10/2021
Dr.
V.P.Shah

107. QUESTIONS
 Conformational changes occur during formation of
oxy Hb
 What is Bohr effect
 Why Hb F high affinity for O2 than Hb A
 What is Glyco-Hb & its significance
 Why does person with sickle cell anemia show
increased resistance to malaria
 Give factors affecting severity of sickling
 What is Hb M
4/10/2021
Dr.
V.P.Shah