Wednesday, November 21, 2007

How To:   Search the SMGF mtDNA database

courtesy Ann Turner, co-author Trace Your Roots With DNA, founder of Rootsweb's Genealogy-DNA mailing list.
Open the SMGF mtDNA Search window by clicking here.

Pick "Other" for the testing company.

Check all HV regions.

Click on "Search by surname" and enter the least common name in your pedigree.

Click on "Clear Values".

Click on Search.

Locate the record with your pedigree. You can usually tell by looking at the surnames and locations, but you can click on the pedigree icon if necessary.

Print out the results screen. It shows where ANY record on the results page has a difference from the CRS.    The CRS value is shown in a faint gray font.

Look at the columns where your pedigree shows a purple box (i.e. a difference
from the CRS).

I like to turn the printout sideways and jot down the most likely substitution right by the locus (the vertical blue numbers).    I use a ruler or another piece of paper as a guideline to be sure I'm lining things up right.

If the CRS is C, put T
If the CRS is T, put C
If the CRS is G, put A
If the CRS is A, put G

If you have insertions compared to the CRS at 16193, 309 or 315 (numbers after a decimal point), put C.

If you have a deletion compared to the CRS at 523 & 524, put "d".

If you have an insertion at 524, put A for 524.1 and C for 524.2 (and keep the A-C pattern going if you have more than one set of insertions).

Click on "Search Again" and enter all the positions where you wrote down a change.    That counts as one query against your daily quota.

Click on "Search."

The vast majority of the time, you will see a perfect match for your sample.    If the most likely substitution didn't work, then try the remaining bases until you achieve a perfect match.

Click on "Search Again".

This time click the radio button on "Search by Differences" so the surname gets grayed out.    To confirm your search, click on "None."

Click on "Search" to see your matches.    If you don't have many matches, you might like to broaden your search to one or two differences.    Some mismatches (e.g. insertions at 309.1C) are rather insignificant.

If your pedigree does not show up, this may be because you only have partial results.    Check again when the next database update is released.


Let me know if I've skipped a crucial step, or if you encounter some cases that aren't covered.

If you have mtDNA results from another testing company, you can enter those directly and see if your pedigree shows up in the SMGF database.


Once you have found yourself by identifying your pedigree send me a TinyURL for your results.

To do that, copy the gigantic URL that appears on the results page.

Open TinyURL by clicking here and paste your gigantic URL into the box indicated.

Click "Make a TinyURL!"

Copy your result and then click here and paste your result into the email to me for posting to the Berry Family DNA Project mtResults page.


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