1 / 11

Dapo Adegbile Nevin Varghese Victor Veras

Dapo Adegbile Nevin Varghese Victor Veras. 1-28-10 Period 2. Summary of Polydactyly. Polydactyly is a condition in which a person has more than five fingers per hand or five toes per foot.

diamond
Download Presentation

Dapo Adegbile Nevin Varghese Victor Veras

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. DapoAdegbileNevin Varghese Victor Veras 1-28-10 Period 2

  2. Summary of Polydactyly • Polydactyly is a condition in which a person has more than five fingers per hand or five toes per foot. • Polydactyly occurs in the womb; instead of developing only one thumb and four fingers an extra finger is added • Usually the hand is formed in the womb and when it is being split it is made into 4 fingers, 1 thumb. However sometimes an extra split occurs and abnormal number of fingers is produced • It is a autosomal dominate characteristic

  3. Chromosome Disorder is Located on • The cause of the disorder is usually found on chromosome 13. • However for some cases it is not known • There is another gene or chromosome that the mutation could happen in that could cause polydactyly

  4. Mode of Inheritance • Polydactyly is autosomal dominant. • Autosomal dominant means that an offspring can get this disease by having it passed down from just one parent. • Polydactyly occurs because of genetic disorders or errors in fetal development. • Polydactyly can also be a symptom for another disease. • Ex. – Bardet-Biedl syndrome • Ex. – Bloom’s syndrome • Ex. – Jeune’s thoracic dystrophy syndrome

  5. What are Alleles? • A person has two alleles per gene • You get one of the two alleles in a gene from your father and the other from your mother • Recessive alleles are represented by the letter of the characteristic in lower-case form • Dominant alleles are represented by the letter of the characteristic in capital • R – Dominant • r – Recessive • The dominant alleles and the recessive alleles both represent two different possible characteristics. • The “characteristic” will be dominant if the gene has one dominant allele or two dominant alleles • The “characteristic” will be recessive if the gene has two recessive genes only

  6. Punnent Square – Demonstration G g w w h h G g W W h h Heterozygous Homozygous

  7. Probabiliy of Disease occuring G g • Ratio • 1GG 2Gg 1gg G g • Percentage • 25% -GG 50% - Gg 25% - gg • 75% chance of getting Polydactyly • 25% chance of not getting Polydactyly

  8. What the letters mean G g • GG – two dominant alleles • Gg – one dominant allele and one recessive allele • gg – two recessive alleles G g • Phenotype • GG = Get polydactyly • Gg = Get polydactyly • gg = normal amount of fingers • Top – Father • Bottom – Mother • Genotype • GG = Homozygous dominant • Gg = Heterozygous dominant • gg= Homozygous recessive

  9. Genotype and Phenotype possibility G g G g • Phenotype • - Ratios- 3 for polydactyly : 1 for normal • - Percentage – 75% chance of polydactyly • 25% chance of normal # of f fingers • Genotype • - Ratios- 1 GG : 2 Gg : 1 gg • - Percentages- 25% GG : 50% Gg : 25%gg

  10. Student Practice G G • Phenotypes • Ratio – • Percentage – G g • Genotypes • Ratio – • Percentage –

More Related