Following are nine common myths regarding lethal white syndrome. The correct information is provided by the University of Minnesota Equine Genetics Group. Myth #1:
All overo horses are carriers of the lethal allele.
Fact: There are many overos that do not carry the lethal allele. Myth #2:
Twenty-five percent of foals from two overo parents will be lethal whites.
Fact: Because there are overos that do not carry the allele, the incidence of lethal white syndrome is less than 25 percent in overo-to-overo matings. Myth #3:
Registered tobianos, Solid-colored Horses, or Paint crosses cannot carry the lethal allele.
Fact: There are tobianos that have overo bloodlines, and these horses can be carriers of the lethal allele. Solid-colored Horses and Paint crosses can carry the lethal allele. Myth #4:
Totally white Paints are not carriers of the lethal allele.
Fact: These white horses are often carriers of the lethal allele. Myth #5:
All totally white foals born to two overo parents are lethal whites.
Fact: There are totally white Paints that are not affected by the lethal white syndrome. Myth #6:
Mares cannot produce lethal foals in consecutive years.
Fact: The genetic make-up of one foal does not affect subsequent births. Myth #7:
Only one parent determines if a foal will be a lethal white.
Fact: Both sire and dam contribute a copy of the lethal allele. Myth #8:
Crop-out Quarter Horses cannot carry the lethal allele.
Fact: A small number of crop-outs have been tested and found to be carriers of the lethal allele. Myth #9:
You can reliably tell the carrier status of a Paint by their color pattern.
Fact: This is false.