Sickle Cell Anemia
description
Transcript of Sickle Cell Anemia
By: Dasia Davis
Gabriella Mirenda
Lorena Sposato
Inherited blood disorder that affects red blood cells Red blood cells contain Hemoglobin S which is abnormal - Become sickle shape and makes it difficult fitting through
small blood vessels and less blood reaches body. Symptoms of sickle cell include
1. Abdominal Pain2. Delayed growth and puberty3. Bone Pain4. Breathlessness5. Fever6. Jaundice
7. Paleness8. Ulcer in the lower legs
Interesting facts: with each pregnancy, 2 people have sickle cell traits have: A 25% chance of having an unaffected child with normal
hemoglobin A 50% chance of having a child who also is a carrier. A 25% chance of having a child with sickle cell anemia
The HBB gene is found in the region 15.5 on the short (p) arm of human Chromosome 11.
Autosomal Recessive genetic disorder Two copies of the altered gene must be
present on the autosomes in order for the person to be affected by the trait.
2 alleles, one from each parent Alleles are represented by: -RR Rr rr Dominant- expressed in a person with
only one copy of that gene present. Recessive- expressed in a person with
two copies of the gene is present.
dd dd
dd dd
Ss ss
ss ss
s
s
Ss
d ddd
SS Ss
Ss ssS
S
s
sRatios:Homozygous dominant: Heterozygous dominant: Homozygous recessive
1 : 2 : 1 1SS : 2Ss : 1ss
Percentages:Homozygous dominant: Heterozygous dominant: Homozygous recessive
25% : 50% : 25% 25% SS : 50%Ss : 25% ss
SS represents the dominant allele SICKLE and s represents the recessive allele
Phenotype: SS= No disease Ss= Sickle cell anemia ss= Sickle cell anemia Genotype: SS=Homozygous dominant Ss=Heterozygous dominant Ss=Homozygous recessive
SS Ss
Ss ssS
S s
s
Phenotype -Ratios- 3SS: 1ss -Percentages: 75% SS: 25% ss Genotype -Ratio- 1SS: 2Ss: 1ss -Percentages- 25% SS: 50%Ss: 25%ss
SS SsSs ss
SSs
s
Father’s GenesM
O
T
H
E
R’
S
G
E
N
E
S
SS
s
sGenotype: Ratio: Percentage:
Phenotype: Ratio: Percentage:
SS
SsS
sss
3SS: 1ss75%SS: 25% ss
1SS: 2Ss: 1ss 25%SS: 50%Ss: 25%ss
SarahRicky Martin
CarlLizzie Alex Miranda
Bob Marley
Vanessa
Cashmere
Red= Person is Healthy, with a possible chance of carrying a “bad” gene.Yellow= Person is affected
Fergie
Zac
KEY Circle: Female
Square: Male
All Red: Person is healthy.
All Yellow: Person is affected.
Red/Yellow: Carrier.
Questions: Answers:
Kim Bob
Brian Lily
Gaby Kait Ana Ben Susan
Charlie Jen
2.) What does it mean, when a person is a “carrier” of the gene?
• It means the person carries one “bad” gene and one “healthy” gene, but is essentially healthy and has no symptoms of the disease.
1.) How many sickle cell genes are need to inherit the disease?
• It occurs when a person inherits two sickle cell genes.