Well the thing is that Punjabi, Sindhi, Seraiki or Mahajir are not ethnicities, races or lineages. They are basically geographical and cultural identities.
Ethnicities, races and lineages are what we know as Jats, Gujjars, Rajputs, Awans, Arains, Kambohs, Pushtuns, Baloch etc and Jats, Gujjars...