Family Group vs Group
Family Groups and Groups are two ways to label relatives and DNA segments.
Group names are assigned to one or more DNA segments, and multiple Group names can be assigned to the DNA segments between one Profile and one relative.
Family Groups are assigned to a Relative record, meaning that any relative with or without chromosomal data, can have any Family Group identifier, enabling them to be clumped together with other relatives with the same Family Group identifier.
The two can operate independently of each other, but can also work in conjunction with each other.
Each can have the same set of names used, or can have unique names.
Each can be set by GDAT, and each can be customised by the user.
Some other features of GDAT do require consistency in naming across multiple points, and as such, it can be easier to allow GDAT to set the names.
Whether the program sets the names, or you set them, is 100% up to you, and you can change them at any time.
Examples of Group Name and Family Groups usage
Double Connection
Here we can see that this match to the profile person is a double connection. The chr 4 segment is known to have come from the maternal grandmother of the profile person, while the chr 10 segment is known to have come from the maternal grandfather of the profile person.
As such, the two segments have been given different Group names of the user's own choosing as it is not yet know how this person connects to the profile person on either inheritance path.
In the instance of a match who is a double connection to the profile, it could be misleading to assign a family group that indicates one path over the other. A custom Family Group name, along with an MRCA Note can prove helpful.
You may also notice the custom status of "Double Connection" that has been given to this match. You may choose to assign one of the default status or create one of your own if you have a similar situation, or you may choose to use the Family Group to reflect the Double Connection aspect.
This person with these Group and Family Group designations as they currently stand, would not appear in a Parental Confirmation view. Further work is needed to identify the MRCA source of each DNA segment, and on finding that source, the current names can be updated to reflect the new knowledge.
In the next example we have a match for whom we have ICW / Triangulation clues as to their potential MRCA source.
One option available, is to mark the Side, and assign a group that is derived from but not identical to the closest known groups of the Triangulated / ICW relatives. Another possible option, would be to use a more distantly connected but still known triangulated relative, and base the group name on this information.
In both cases, the Group name is assigned to a DNA segment and will appear on the chromosome view. In both cases also, the same designation could be included in the Family Group area on the Notes view.
The first option is to use the closest known group of "Tertius-Quartus" , and mark the currently unknown relative with the group name of "Tert-Quar Anc" - indicating that this relative is connected somewhere along the Tertius-Quartus branches of the tree.
The other option is to use the "Septimus-Caelius" indication that is further up the Tertius branch, and is not connected to the Quartus branch. Meaning we could either tweak the group name to indicate a Tertius ancestral connection, or we could further fine tune the grouping and use "Sept-Cael Anc".
Personal preference applies to the use of these areas for matches that have not yet been fully determined as to their relationship and position in your tree.