What DNA (especially the Y Chromosome)

Can Tell Us

DNA Technology

•DNA Isolation

•Break apart membranes

•Remove proteins

•Precipitate DNA with alcohol

DNA Technology•Amplifying a

Segment of DNA

•In vivo methods

•cloning in bacteria, yeast, ...

•In vitro methods

•PCR (the polymerase chain reaction)

DNA Technology

•Visualizing the DNA

•Gel electrophoresis

DNA Technology•Reading the

DNA Fragment

•DNA sequencing

•Genome sequencing

What DNA (especially the Y Chromosome)

Can Tell Us

Mining the Past

•Using Ancient DNA

•Using the DNA of Descendants

DNA & Heredity

•DNA is the Genetic Material

•Most genes are on non-sex chromosomes (autosomes) in the nucleus

•Some genes are on sex chromosomes (X & Y) in the nucleus

DNA & Heredity•Autosomal Chromosomes

•Recombination (crossing over) makes the picture of your DNA’s past complex

•One of your #1 chromosomes is from your mother, one from your father, but...

•Due to recombination, that maternal chromosome is from both of your maternal grandparents...

•Autosomal Chromosomes

DNA & Heredity: the Y

•A Male’s Y Chromosome Has a Simpler History

•The Y does not (usually) undergo recombination, so your Y is exactly like your father’s, your paternal grandfather’s,... (except for rare mutational events)

•Y Chromosome

•These Very Rare Mutational Events Are Traceable

•Single Nucleotide Polymorphisms (SNPs) -- single base changes

•Indels (insertions and deletions)

•Others, like variations in the number of repeated units

DNA & Heredity: the Y

•A Set of These Variations on One Y is a Haplotype

•Haplotypes Reveal the History of the Y Chromosome

• Phylogenies can be built based on the fewest mutational events needed to produce the different haplotypes seen (haplogroups)

•With assumptions, the time since divergence can be estimated

DNA & Heredity: the Y

•Y Chromosome

•Y Chromosome

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