Manx Genealogy

Vannan surname

I am wondering if anyone knows something about my surname, Vannan?
My father's family came to the USA in 1910, from Glasgow, Scotland. Research indicates that the surname Vannan originated on the Isle on Man.
I can trace ancestor James Vannan (ggf) to Wymmus Plack, Scotland around 1900. Although there is no mention of his wife, Mrs. James Vannan at that time.
Her name was Elizabeth Sharp (Vannan)
My grandfather was named with his mothers surname as James Sharp Vannan.
Any help would be greatly appreciated. Thank you and God bless.