I don't think they are anything like the Gumuz or Dinkas (who are highly Nilotic). Only some haplogroup studies on them, nothing autosomal. I think they are closer to mainstream Horners than to full Nilotes like the Dinka, Gumuz etc. @kobe
The Nara are linguistically closest to Nubians, and Nubians are another Nilo-Saharan group very close to Afro-Asiatic Horners.
Northern Eastern Sudanic languages - Wikipedia
en.wikipedia.org
They definitely look like they have a fair amount of Horner admixture. The famous Muslim Eritrean freedom fighter Hamid Idris Awate was said to be a Nara and Beni Amer (Beja-Tigre tribe) mix
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