tay-sachs disease

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TAY-SACHS DISEASE GENETIC DISORDERS MIGUEL URBINO & JAZZ RANDALL PERIOD 3

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GENETIC DISORDERS. MIGUEL URBINO & JAZZ RANDALL PERIOD 3. TAY-SACHS DISEASE. PLEASE KEEP IN MIND. OTHER PEOPLE MAY Have THIS DISEASE AND BE RESPECTFUL WHEN REACTING . SUMMARY. Very rare This disorder is inherited It destroys the nerve cells in your brain and spinal cord - PowerPoint PPT Presentation

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Page 1: TAY-SACHS DISEASE

TAY-SACHS DISEASEGENETIC DISORDERS

MIGUEL URBINO & JAZZ RANDALLPERIOD 3

Page 2: TAY-SACHS DISEASE

OTHER PEOPLE MAY HAVE THIS DISEASE AND BE RESPECTFUL WHEN REACTING

PLEASE KEEP IN MIND

Page 3: TAY-SACHS DISEASE

SUMMARY• Very rare• This disorder is inherited• It destroys the nerve cells in your brain and

spinal cord• Recessive gene • Mostly occurs in infants• Survival rate is up to 3 to 4 years of age

Page 4: TAY-SACHS DISEASE

INFANTS

• Lose their motor skill ability such as turning over, sitting, and crawling

• Exaggerated startled reactions to loud noises • Not easily noticed at first• Go through seizures, vision and hearing loss,

intellectual disability, and paralysis

Page 5: TAY-SACHS DISEASE

CHROMOSOME 15

The HEXA- Chromosome 15Tay Sachs is caused by mutations in the HEXA gene

Page 6: TAY-SACHS DISEASE

MODE OF INHERITANCE How would one acquire Tay Sachs? -if the parents of an offspring are both a carrier of the disease then

you get full Tay Sachs What does sex linked/x-linked, autosomal recessive or autosomal

dominant mean? - If a disease is autosomal dominant, it means you only need to get the gene

from one parent in order for you to inherit the disease. - An autosomal recessive disorder means two copies of the gene must be

shown in order for you to inherit the disease or trait. - Sex-linked means that a single gene on the X chromosome can cause the

disease. This can happen in boys and girls but in the case of males they may not survive.

Page 7: TAY-SACHS DISEASE

ALLELES• An allele is an alternative form of a gene that is located at a specific

position on a specific chromosome• 2/per gene• They come from our parents whether they carry the trait or not• Recessive= r Dominate= R• Dominant means you are more likely to inherit something from your

parents• Recessive means you can inherit it from your parents but it is a less

likelihood you will

Page 8: TAY-SACHS DISEASE

PUNNETT SQUARESFATHER'S GENES

T t

MOTHER'S T TT Tt

GENES t Tt tt

FATHER'S GENES

T T

MOTHER'S T TT TT

GENES t Tt Tt

FATHER'S GENES

T T

MOTHER'S T TT TT

GENES T TT TT

FATHER'S GENES

t t

MOTHER'S T Tt Tt

GENES t tt tt

Page 9: TAY-SACHS DISEASE

Ratios: 1 : 2 : 11TT : 2Tt : 1t

FATHER'S GENES

T t

MOTHER'S T TT Tt

GENES t Tt tt

ANALYZING PUNNETT SQUARES

Percentages: 25% : 50% : 25%

25%TT : 50%Tt : 25%t

Page 10: TAY-SACHS DISEASE

ANALYZING PUNNETT SQUARES (CONTINUED)

What do the letters mean?FATHER'S GENES

T t

MOTHER'S T TT Tt

GENES t Tt ttPhenotype: (Physical Color)TT= RedTt = Yellowtt = Green

Genotype:TT = Homozygous DominantTt = Heterozygous Dominant

tt = homozygous recessive

Page 11: TAY-SACHS DISEASE

ANALYZING PUNNETT SQUARES (CONTINUED)

Genotype and PhenotypeFATHER'S GENES

T t

MOTHER'S T TT Tt

GENES t Tt tt

Phenotype: (Physical Color)Ratios- 1 Red : 2 Yellow : 1 GreenPercentages- 25% Red : 50% Yellow : 25% Green

Genotype:Ratios- 1 TT : 2 Tt : 1 tt

Percentages- 25% TT : 50% Tt : 25% tt

Page 12: TAY-SACHS DISEASE

PHENOTYPE:Ratio-Percentages-

FATHER'S GENES

t T

MOTHER'S t

GENES T

PRACTICE PUNNETT PROBLEMS

GENOTYPE:Ratio- Percentages-

Page 13: TAY-SACHS DISEASE

3 GENERATIONHYPOTHETICAL PEDIGREE

LEGEND:• Square = Male• Circle = Female• Red = TT• Yellow = Tt• Green = tt

Page 14: TAY-SACHS DISEASE

PEDIGREE PRACTICELEGEND:• Square =• Circle =• Shaded =• Half Shaded = • Not Shaded =

ANALYZING PEDIGREES Read the Questions CAREFULLY

1. Is it possible for a TT and Tt to have a tt off-spring?2. Is it possible for a Tt and Tt to have a TT off-spring?3. Is it possible for a tt and TT to have a TT off-spring?

Page 15: TAY-SACHS DISEASE

THANK YOU FOR YOURATTENTION AND COOPERATION MIGUEL URBINO & JAZZ RANDALLPERIOD 3