Linkage Mapping and a few odds and ends

Linkage, Mapping, and a few odds and ends Bonus #2 due 11/25 Exam #3 T 12/2 in class (bring cheat sheet) Final Sat. 12/6 from 9 am – 12 noon in BIO 301

Linkage can be used to determine distance Homologous pair of chromosomes

Some crosses do not give the expected results

By comparing recombination frequencies, a linkage map can be constructed = 17 m. u.

Fig 5. 2

The probability of crossing over can be used to determine the spatial relationship of different genes

Double recombinants arise from two crossovers Recombinant

Double recombinants can show gene order

What is the relationship between these 3 genes? What order and how far apart? similar to Fig 5. 3, also see Fig 5. 9, and pg 115 -117

What is the relationship between these 3 genes? What order and how far apart? similar to Fig 5. 3

Double crossover

Which order produces the double crossover?

Which order produces the double crossover?

We have the order. What is the distance?

Recombinants between st and ss: (50+52+5+3)/755 =14. 6%

Recombinants between ss and e: (43+41+5+3)/755 =12. 2%

Put it all together… 26. 8 m. u. st ss 14. 6 m. u. e 12. 2 m. u.

Drosophila linkage map

Linkage map of Drosophila chromosome 2

Recombination is not completely random. physical distance Yeast chromosome 3 linkage map

Alignment of physical and recombination maps

Genotype Phenotype Genes code for proteins (or RNA). These gene products give rise to traits… It is rarely this simple.

{Meiosis: producing gametes} For life to exist, the information (genes) must be passed on. {Mitosis: producing more cells}

105 males : 100 females (live births) Why?

105 males : 100 females (live births) Why?

Is this all of your DNA?

Fig 7. 13 Mitochondria have their own DNA.

Endosymbiotic Theory - proposed origin of mitochondria and chloroplasts from free-living bacteria to cellular organelles Fig 7. 20

Human Life Cycle Combination of two individuals DNA

Only the egg provides mitochondria to the offspring. mitochondria

Human Life Cycle In females Mom provides 50. 000275% and Dad provides 49. 999825% of DNA to offspring. … because Mom provides 100% of mitochondrial DNA

Mitochondrial DNA comparisons can be used to trace ancestry:

During the Bolshevik revolution, the Tsar’s family was captured and executed. Tsar’s Family

There are many stories about what happened to their youngest daughter Anastasia Tsar’s Family

Anna Anderson, claimed she was Anastasia

Anna Anderson claimed she was Anastasia, but tests of her mt. DNA and one of Anastasia’s maternal relatives did not match.

For more info check out: http: //en. wikipedia. org/wiki/Grand_Duchess_Anastasia_Nikolaevna_of_Russia Or the book “Seven Daughters of Eve” by Bryan Sykes

How do individuals and groups with different genes arise? Evolution… Does it occur? How does it occur?

Linkage, Mapping, and a few odds and ends Bonus #2 due 11/25 Exam #3 T 12/2 in class (bring cheat sheet) Final Sat. 12/6 from 9 am – 12 noon in BIO 301