- There are 4 main blood groups: A, B, AB, and O determined by alleles. - A mother with blood group A and a father with blood group B will have children that are all blood group AB. - A father with blood group O and a mother with blood group A will have children with blood groups AO and OO. - The Rhesus (Rh) factor is either positive or negative and Rh+ is dominant over Rh-. A Rh- mother and Rh+ father can have Rh+ or Rh- children.

2. Blood group
• 4 blood groups:
A – allele : AA or AO
B – allele : BB or BO
AB – allele : AB
O – allele :OO ( O recessive)

3. Blood group inheritance
• If a mother has blood group A and the
father has blood group B, what are the
blood groups of their children?

4. Answer
• If the mother is A, the genotype of her
blood is AA or AO
• If the father is B, the genotype of her is
BB or BO

5. • Cross between AA and BB = all children
will be AB
• Cross between AA and BO = the children
will be AO or AB = ?
• ?

6. If the father has O blood group, and the
mother has A, what are the blood groups
of their children?

7. Answer
• Father : O, genotype : OO
• Mother : A, genotype: AO or AA
• Children :
– AO X OO = AO and OO
– AA X OO = AO and AO

8. Rhesus factor inheritance
• Rhesus = Rh
• Rh + = has antigen of Rhesus
in erythrocyte ( dominant)
• Rh - = no antigen of Rhesus but able to
produce antibody if stimulate by
antigen. Antibody present in the
blood

9. Rh inheritance
Mother : Rh - ( rh rh) X Father (Rh Rh)
• Foetus : Rh+ Rh-
Rh dominance.

10. Rhesus inheritance
Rh +
Rh -

11. Mother; Rh +ve, foetus : Rh -ve
• Mother antigen in RBC unable to
diffuse through placenta
• Baby born alive

12. Rh -
Rh +

13. If mother Rh –
and foetus is Rh +
• During delivery, some of the baby blood in
the placenta mixed with mother blood
• The 1st
baby will be born alive
• Rhesus antigen in RBC will enter the
mother blood system
• The lymphocyte in the mother system will
be stimulated and produce antibody.

14. • Antibody will remain in mother blood
plasma
• In second pregnancy, the Rh + foetus Rh+
in RBC
• Antibody from the mother blood plasma
able to diffuse into foetus blood through
placenta
• Agglutination occurs in foetus blood
• Causing the premature dead of the foetus

16. Inheritance of sickle cell anemia
• Caused by recessive allele
• Located on autosome

19. Thalasemia

21. Sex inheritance
• Somatic cell has 23 pairs of chromosomes
• 22 pairs are autosomes
• 1 pair is sex chromosome (X and Y)
• Kromosom seks = kromosom X dan Y
• Male:
44 autosome + XY
• Female:
44 autosom + XX

22. Chromosome in the cell during
cell division

24. Female karyotype ?

25. • Same as male
• The 23rd
pair is XX

27. Sex inheritance
• How sex of the child is determine?
mother X father
44 + XX 44 + XY
Ovum: 22 + X Sperm: 22 + X or 22 + Y
Child ?
Percentage of chance ?

28. Child ;
• 44 + XX is a girl
• 44 + XY is a boy
• Percentage of chance:
1/2 girls : 1/2 boys
50 % : 50%

30. Sex – linkage gene
• Most of the allele that control the disease
is:
– Recessive
– Located in X chromosome
• If two recessive allele pairs up, the
disease will appear
• For male, the present of an allele on X is
enough to cause the disease.

32. Heamophilia
Color blindness

34. Heamophilia

37. The colour blindness
inheritance