Timing of mutations - and poor explanations

[joeflood]

Im now getting a "New Topic" button so Ill post again.

Although Im a scientist, Im finding it hard to work out what is going on in the literature which is jargon-filled with few explanations. For example it took me a long time to work out that haplotypes are based on simple binary markers called SNPs whereas what we are testing is SSRs (simple sequence repeats). As it's rarely explained anywhere, this made it hard initially for me to work out what familtreedna was talking about when it came to subclade testing.

Now my first question is - how do they know for example that haplotype B is descended from A and not the other way round? And how can they possibly time when the mutation occurred?

My second question relates to "microsatellites" and "minisatellites" which a number of papers are using to test recent human migration. Im inclined to think, after some research, that these are just another word for SSRs. Are they? And how can they be used to time various genetic events (such as whether various British DNA or communities came from Saxons or Romans) as some papers aver?

[Rapp]

I am also a scientist and have some questions, but few answers.

I had only seven low-resolution Mt-DNA (H haplogroup) matches, and these were spread around northern Europe and America (English-Scottish).  My wife had 464 low resolution matches (T haplogroup), and they were also spread around Europe and America with many of them coming out of eastern Europe (Russian-German).  The "H" group is alleged to be more common in Europe than the "T" group, and I would assume that more western Europeans and Americans do DNA testing than eastern Europeans.  Why so few hits on my "H" Mt-DNA?

The same is true for my Y-DNA.  I had 11 12/12-factor (R1b1c) matches (Scot-Irish), and only one 24/25-factor match, and this guy thinks that he is French.  There were no surname matches, just English, Scottish, and Irish names.  A friend of mine had dozens and dozens of 12/12, 25/25, and 37/37-factor Y-DNA (I) matches.  HE also had many surname matches.

Could the fact that I have so few Y-DNA and Mt-DNA matches be the result of late mutations on both sides of my family?

Confused in northern California.

[Biscuits]

I moved this post from "Question of the Week" to "General Discussion" as part of some forum maintenance.  "Question of the Week" is supposed to be a place for all the news articles and questions that WorldFamilies administrators post on our main webpage, while "General Discussion" is supposed to be a place for users to start their own topics.  Both sets of posts were mixed together, and I just did the laborious job of separating them.

I'm hoping that the forums will be easier to use in their new format.  It should be simpler for users to discover what's new on the website and, thus, it should be easier for folks to stay involved here.  This is just a small part of the overhaul we're doing to the forums, and you should expect to see a great many improvements in the coming days and weeks.  Thanks for being patient, and I apologize for any inconvenience that I may have caused.