Definition of welt. 1 : a strip between a shoe sole and upper through which they are stitched or stapled together. 2 : a doubled edge, strip, insert, or seam (as on a garment) for ornament or reinforcement. 3a : a ridge or lump raised on the body (as by a blow or allergic reaction)b : a heavy blow.
The list of signs and symptoms mentioned in various sources for Polydactyly includes the 4 symptoms listed below: 1  More toes than normal. 2  More fingers than normal. 3  Extra digit on hand. 4  Extra digit on foot. 5  more information...Â».
Genetic Drift and the Founder Effect. Polydactyly -- extra fingers or sometimes toes -- is one symptom of Ellis-van Creveld syndrome. The syndrome is commonly found among the Old Order Amish of Pennsylvania, a population that experiences the founder effect..