Presentation on theme: "By: Dasia Davis Gabriella Mirenda Lorena Sposato."— Presentation transcript:
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 Pain 2. Delayed growth and puberty 3. Bone Pain 4. Breathlessness 5. Fever 6. Jaundice 7. Paleness 8. 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.
SS SsSs Ssss S S s s Ratios: 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 SsSs Ssss S S s s
PPhenotype -Ratios- 3SS: 1ss -Percentages: 75% SS: 25% ss GGenotype -Ratio- 1SS: 2Ss: 1ss -Percentages- 25% SS: 50%Ss: 25%ss SS SsSs Ssss S S s s
Father’s Genes M O T H E R’ S G E N E S S S s s Genotype: Ratio: Percentage: Phenotype: Ratio: Percentage: SSSs ss 3SS: 1ss 75%SS: 25% ss 1SS: 2Ss: 1ss 25%SS: 50%Ss: 25%ss
Sarah Ricky Martin Carl LizzieAlex 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 BrianLily GabyKaitAna 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.