Shedding

The dogs coat structure and length are influenced by several known genetic traits. A variant found in the MC5R gene is associated with the shedding of the hair, as well as the coat length.
The recessive allele for shedding (sh-allele) is found in breeds that show heavy shedding (genotype sh/sh). Dogs with at least one N-allele for non-shedding loose significantly less hair.
The furnishing variant of the RSPO2 gene influences the shedding too. Dogs that possess the homozygous dominant furnishing genotype F/F do not show heavy shedding, irrespective of the genotype on the MC5R gene.
Coat length is mainly influenced by several recessive variants on the FGF5 gene (coat length locus) and the dominant furnishing variant on the RSPO2 gene. Additionally, the shedding variant on the MC5R gene was found as a factor for the hair-length.
Longer coat is associated with the recessive l-allele (long-haired), the dominant F-allele (furnished) and the recessive sh-allele (shedding), while short hair correlates with the dominant L-allele (short-haired), the recessive f-allele (unfurnished) and the dominant N-allele (non-shedding).
Medium hair-length in some genetically short-haired (FGF5 L/L or L/l) and unfurnished breeds from the shepherd or retriever group might be explained by the shedding variant of MC5R.