African Eve Gets Lost in the 'Trees.' (Mitochondrial DNA Research)

Science News, February 22, 1992 | Go to article overview
Save to active project

African Eve Gets Lost in the 'Trees.' (Mitochondrial DNA Research)


Since 1987, an influential group of molecular biologists has published several reports indicating that analyses of mitochondrial DNA -- genetic material located outside the cell nucleus and inherited only from the mother -- track the maternal lineage of all humans back to one or possibly several women who lived in Africa around 200,000 years ago (SN: 9/28/91, p.197). That controversial contention gets the statistical rug pulled out from under it in two reanalyses of the most extensive sample of mitochondrial DNA studied earlier. The new findings appear in Feb. 7 SCIENCE.

One study, directed by S. Blair Hedges of Pennsylvania State University in University Park, builds five mitochondrial DNA trees but fails to pinpoint statistically the geographic origins of humanity. Particular sequences of chemical components of mitochondrial DNA appear about as often in all geographically separated populations, Hedges' team argues. This, they say, suggests that widely separated human groups have shared, or conserved, specific chemical arrangements of mitochondrial DNA since those populations diverged from a single group. Analyses of DNA sequences from within the cell nucleus may offer a better possibility of establishing a valid evolutionary tree for humanity, the scientists hold.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited article

African Eve Gets Lost in the 'Trees.' (Mitochondrial DNA Research)
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?