The rules of vowel harmony may vary by regional dialect. The dialect of Turkish spoken in the Trabzon region of northeastern Turkey follows the reduced vowel harmony of Old Anatolian Turkish, with the additional complication of two missing vowels (ü and ı), thus there is no palatal harmony. It's likely that "elün" meant "your hand" in Old Anatolian. While the 2nd person singular possessive would vary between back and front vowel, -ün or -un, as in "elün" for "your hand" and "kitabun" for "your book", the lack of ü vowel in the Trabzon dialect means -un would be used in both of these cases — "elun" and "kitabun".