Alaskan Malamutes are prone to losing pigment on their nose and muzzle — this can be caused by nasal solar dermatitis, vitiligo, or lupus, but most commonly it's a harmless condition called snow nose where the nose only loses pigment in the winter. (yourpurebredpuppy.com)
It is possible for a yellow dog to have a red nose, and «pass» as a normal (or possibly light) red (see Yellow Lab pigment - Woodhaven Labradors for a picture - also has a information on snow nose). (lethalwhites.com)
In fact, even though the American Kennel Club lists a black nose as a requirement for huskies, it allows them to compete with snow nose. (countryliving.com)