How and why can mitochondrial DNA be

used to trace family ancestry?By Ali, Lara, and Jeremy

Overview of Mitochondrial DNA to Family Ancestry

What does mitochondrial DNA help us achieve?With mitochondrial DNA we can trace a person’s maternal family

ancestry.Using mitochondrial DNA we have been able to achieve as far back as

a common ancestor of all human beings. Using mitochondrial DNA we are also able to track our family’s

ancestor’s migration patterns (where they traveled/moved)

What question are we trying to answer using mtDNA?We are trying to discover our maternal family ancestor. By using mitochondrial DNA we are able to discover where we came

from and who we are.

History and Major Points

1960: Mitochondrial DNA was discovered using electron microscopy and biochemical assays.

1987: Using Mitochondrial DNA, the Mitochondrial Eve was discovered. This links all humans to one common maternal ancestor.

The science behind using mitochondrial DNA to trace family ancestry• What is Mitochondrial DNA?• DNA found in mitochondrion• Only mother passes on mitochondrial DNA to offspring

• Ancestral Markers• Mutations in D-loop region• Unique sequences characterize a maternal family line• Analysis of mitochondrial DNA can uncover a person’s ancestral haplogroups and migrations

Analyzing Mitochondrial DNA

• Mitochondrial DNA sequencing• Purification of mitochondrial DNA• Copying and enlarging of D-loop DNA• Gel electrophoresis to identify nucleotide sequence

• SNP testing• Specific questions about maternal lineage• Changes at a single point in genetic code

Is using mitochondrial DNA to trace family ancestry controversial?• Mitochondrial Eve recalculated to have lived 60,000 years ago based

on rate of mitochondrial DNA mutations• Conflicts with results from other well-established methods of dating

early humans • DNA recombination• DNA recombination and faster mitochondrial DNA could disprove

family migration dates and result in miscalculation of ancestral haplogroups• Currently no consensus on mutation rate

How Mitochondrial DNA is currently being used to trace family ancestry

1.Sample Preparation• Remove Contaminants and add lysis solution

2.Mitochondrial DNA Extraction• Organic Chemical detaches empty DNA

3.Polymerase Chain Reaction Amplification• Process in which small DNA are amplified

4.mtDNA Purification and Quantification• Chemical is added that removes excess PCR molecules and sample

is quantified (measured) to determine concentration of amplified empty DNA region

5.Sequencing• Empty DNA double strand is denatured into 2 single strands which undergo PCR. Scientists tag the

desired strand and then with Gel electrophoresis scientists separate DNA fragments

The future potential of tracing mtDNA back to our ancestors• Mitochondrial Eve

• Theory that every human is related to each other• Mother than connects us all is Mitochondrial Eve

• Potential of tracing empty DNA will eventually

lead to the discovery of one’s family lineage

• The biotechnology can answer who we are and where we

we came from?

Bibliography (for Images)

• Mitochondria. Photograph. Learning Center. 2014. Accessed January 2, 2014. http://www.genebase.com/learning/article/18.

• MtDNA SNP Mutation. Image. Learning Center. 2014. Accessed January 2, 2014. http://www.genebase.com/learning/article/ 18.

• Oppenheimer, Stephen. "Mitochondrial DNA: The Eve Gene." Mitochondrial Eve. Accessed January 8, 2014. http://www.bradshawfoundation.com/journey/ eve.html.

• Inheritance Pattern of mtDNA. Photograph. Learning Center. 2014. Accessed January 5, 2014. http://www.genebase.com/learning/article/17.