|If you use Family Tree Maker, you can generate specific Gedcoms. For example - I am arranging a Family Reunion for my half-sister's mother's family & cousins we have found through DNA Matches... To get just her mother's lines from mine I start by going to her mother's profile and Ticking to request her ancestors & descendants; then I go to the top of all of the ancestral lines and Tick on the Descendants of each one... That will generate me a full Gedcom Tree for my half-sister's side of the family.|
Hope that helps.
By the way - I am having a lot of Gedcom statistical fun at this website: http://gigatrees.com/blog/gigatrees
I am amazed at the Maps it is producing - Locations for each & every person on your Tree to show where they their family lived. Also - for each & every person - statistics on Names, Longevity, Census information (10 generations) and much much more - It is an amazing application. Only point of concern is that you cannot make your tree private - so I plan to delete mine soon until they sort out privacy on living people - again - you could create a gedcom without living people for this purpose. Gigatrees is Free to a point, but you get a lot more if you pay a one-time fee of $30.
It's worth a try!