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

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