ancestry vs line of descent

ancestry and line of descent both are nouns.

Word	Noun	Adjective	Verb	Adverb
ancestry	Yes	No	No	No
line of descent	Yes	No	No	No

As nouns, ancestry and line of descent are synonyms defined as:

ancestry and line of descent: the hereditary derivation of an individual

Other synonyms of ancestry include blood, blood line, bloodline, descent, line, lineage, origin, parentage, pedigree, stemma, stock.

ancestry (noun)	line of descent (noun)
inherited properties shared with others of your bloodline	the hereditary derivation of an individual
the hereditary derivation of an individual	the kinship relation between an individual and the individual's progenitors