Information Important to Breeders

There has been a Significant Development in Mode of Inheritance Study! PRA in Mastiffs is a dominant trait, possibly with incomplete penetrance. Second Meagle Diagnosed With PRA!

Since PRA can be undetectable until a Mastiff is 2 years old or older, Mastiffs at high risk for having PRA should not be bred until they have CERFed clear at an older age, or DNA tested clear. All Mastiffs should be CERFed prior to breeding, preferably within a couple months prior to breeding to get the most accurate exam.

Simple Dominant

Dominant means that only one copy of the PRA gene is needed for a dog to have PRA. Simple means all dogs with even one copy of the gene will have PRA (be affected). For a dog to have PRA at least one parent must have at least one copy of the PRA gene.

Statistically:

• when clear dog is bred to dog with one PRA gene, 50% of the puppies will have one PRA gene (have PRA) and 50% will be clear.
• when a dog with one PRA gene is bred to another dog with one PRA gene, 25% of the pups will be clear, 50% will have one PRA gene (have PRA) and 25% will have two PRA genes (have PRA). So, statistically, 75% will have PRA.
• when a dog with two PRA genes is bred to a clear dog, all pups will have one gene for PRA. All will have PRA.
• when a dog with two PRA genes is bred to a dog with one PRA gene, 50% will be have one gene for PRA, and 50% will have two genes for PRA. All will have PRA.
• when two affected dogs are bred together, all of the pups will have PRA.

Dominant with incomplete penetrance

Dominant means that only one copy of the PRA gene is needed for a dog to have PRA. Incomplete penetrance means that the amount of "dominance" varies anywhere from a dog fully expressing the gene to not expressing it at all. I.e., a dog can have the PRA gene and not have PRA - this is rare. If a dog has two copies of the PRA gene all the offspring, regardless of what genes the other parent has will have the PRA gene. For a dog to have PRA at least one parent must have the PRA gene. Some definitions based on dominant with incomplete penetrance inheritance:

• clear - no gene's for PRA
• carrier - 1 gene for PRA, carriers express their PRA gene to varying degrees from full expression to none at all - most will go blind.
• affected - 2 genes for PRA, these dogs will express PRA fully and will go blind.

Statistically:

• when a carrier is bred to a clear dog, 50% of the puppies will be carriers.
• when a carrier is bred to a carrier, 25% of the pups will be clear, 50% will be carriers and 25% will be affected.
• when an affected is bred to a clear, all pups will be carriers.
• when a carrier is bred to an affected, 50% will be carriers, and 50% will be affected.
• when two affected dogs are bred together, all of the pups will have PRA.

Generously shared public information

The following Mastiffs have PRA and their owners have generously agreed to share this information for the betterment of the breed. If you have a Mastiff with PRA, you can match their generosity by mailing a copy of your Mastiff's eye exam sheet and a copy of their AKC registration papers to: Deb Jones, 5951 Huntingtown Rd, Huntingtown, MD 20639 with a signed note asking that they be placed on this page.

Shirley Marquardt  Ironwaysmtfs@QNET.COM

  Her Highness Mastie (female)
      SIRE: Woodleigh's Wells Tobias
       DAM: Stonypoint's Buffalo Girl

Deb Baginski  BlueRoseFarm@netzero.net

  Cedar Ridge Annie Gets Her Way (female)
      SIRE: Ch. Cedar Ridge Rajun Roughrider
       DAM: Cedar Ridge Minnie Mouse

Vicki McGovern  AHDelhihills@Prodigy.net

  Victoria's Girl Cheyanne (female)
      SIRE: Brutus Shy Guy (OFA excellent)
       DAM: Weasel Creek Hanna

Kelly Cooper  roar@nctimes.net

  Cactus Flower Big Roar (male)
      SIRE: Cactus Flower Thor
       DAM: Cactus Flower Hanna

Nanci Manceau  KingmontMastiffs@ns.net

  Ch. Busters Solo Legacy, CD (female)
      SIRE: Buster Of Kingmont
       DAM: Omar V. Herman Babs

Janet Angel

  Midnight Angel (female)
      SIRE: Ch. Moonshadow Blood Sweat And Tears (OFA good)
       DAM: Muffin Of Berg And Tal

Laurie Bunting

  Chantilly Lace The III (female)
      SIRE: Crown Valley's Mycroft
       DAM: Cactus Flower Miranda

Margo Lauritsen  LAMARS3@aol.com

  Ch. Lamar's Sheri Canary (OFA good) (female)
      SIRE: Ch. Byron's Hubba Bubba
       DAM: Ch. Lamar's Silver Streak (CERF90)

  Lamars Dew Ya' Wanna Dance (female)
      SIRE: Ch. Lamar's Odin Of Asgard
       DAM: Lamar's Diamond Geena (OFA fair,OFEL)

  Ch. Lamars Nut'n But Trouble (female)
      SIRE: Int.Am.Can.Ch. Coltons Beauregard (OFA fair,OFEL,CERF75)
       DAM: Ch. Lamar's Little Erica Jill (OFA fair)

Tony and Mecherie McGilvery  mastiff@slip.net

  Ch. Lamar's Odin Of Asgard (male)
      SIRE: Ch. Viceroy's M Cromwell Of Kent (OFA good)
       DAM: Ch. Lamar's Little Erica Jill (OFA fair)

  Ch. Lamar's Talamasca OD Scendant (female)
      SIRE: Ch. Lamar's Odin Of Asgard
       DAM: Lamar's Diamond Geena (OFA fair,OFEL)

Ellen Chen  SCalebotta@aol.com

  Sweetshops Kiwi Bear (female)
      SIRE: Moonshadow Duke Beauregard (OFA good,OFEL)
       DAM: Sweetshops Oki Enu (CERF60)

Harry Cooney  hcooney@wheatstate.com
    Pooh's Page  (316) 782-3484  939 N Oxford Rd,  Udall, KS 67146

  Donachy Morco's Pooh Bear (male)
      SIRE: Ch. Ironlion's Moses Of Donachy (OFA excellent, CERF30&84)
       DAM: A Shobiz Zoe (OFA good, CERF31)

  Donachy Morco's Phoebe (female)
      SIRE: Ch. Ironlion's Moses Of Donachy (OFA excellent, CERF30&84)
       DAM: A Shobiz Zoe (OFA good, CERF31)

Alice Amyx-West  westamyx@mindspring.com
    Hippy's Place  (972) 291-3933  PO Box 1002,  Cedar Hill, TX 75106-1002

  Ch. Meadowrun Dickens (OFA fair) (male)
      SIRE: Ch. Stonebrook Southports Byron (OFA)
       DAM: Wrightous Della

  Ch. A Show Biz Hippolyta (OFA good) (female)
      SIRE: Ch. Stonebrook Southports Byron (OFA)
       DAM: Wrightous Della

  Ch. A ShoBiz Sierra O'Shea (female)
      SIRE: Ch. A Show Biz Sugarpuss O'Shea
       DAM: Ch. A Show Biz Hippolyta (OFA good)

  A ShoBiz Mary Pickford (female)
      SIRE: Ch. A Show Biz Sugarpuss O'Shea
       DAM: Ch. A Show Biz Hippolyta (OFA good)

  A ShoBiz O'Shea's Sugarpuss (male)
      SIRE: Ch. A Show Biz Sugarpuss O'Shea
       DAM: Ch. A Show Biz Hippolyta (OFA good)

  A ShoBiz O'Shea's St Becket (male)
      SIRE: Ch. A Show Biz Sugarpuss O'Shea
       DAM: Ch. A Show Biz Hippolyta (OFA good)

  Meadowrun Tobias George (male)
      SIRE: Ch. Meadowrun Dickens (OFA fair)
       DAM: Ch. A ShoBiz Sierra O'Shea

Karen Flocker   jif2@dana.ucc.nau.edu
    (520) 779-0473   3228 Mehrhoff Pl.,  Flagstaff, AZ 86001
    The Day the Lights Went Out

  Ch. Apple Creeks Ebony Onyx, CD (female)
      SIRE: Ch. Apple Creeks Its Showtime (OFA good,CERF51)
       DAM: Ch. Apple Creeks Southport Kahlua (OFA excellent)

  Ch. Apple CreeksSpirit Of New Begining, CD (female)
      SIRE: Ch. Apple Creeks Sierra (OFA fair)
       DAM: Ch. Apple Creeks Southport Kahlua (OFA excellent)

Cyndi Herzing    cherzing@comwerx.net
   (713) 894-0046  12034 Spring Cypress,  Tomball, TX 77375
   Bubba's Story

  Ch. Omar V. Herman Bubba (OFA excellent,OFEL) (male)
      SIRE: Arciniega's Mystical Sabbath
       DAM: Omar V. Herman Darby

Ron & Caroline Tobin   RONTOBIN@aol.com
    (805) 498-6135   1248 Comstock Pl.,  Newbury Park, CA 91320

  Ch. Comstocks Maiden Voyage, CGC,TDI (OFA good) (female)
      SIRE: Ch. Southports Black Orpheus (OFA fair)
       DAM: Ch. Southports Comstock Velvet (OFA good)

  Comstocks Sweet Serenity (female)
      SIRE: Ch. Southports Black Orpheus (OFA fair)
       DAM: Ch. Southports Comstock Velvet (OFA good)

Kelly Hayes    (503) 324-6028  PO Box 391,  Banks, OR 07106

  Lamar's Budrick Of West Shore (OFA fair) (male)
      SIRE: Lamar's Brandon Le'Moose
       DAM: Knightsens Lamar's Sahdi Blu

Laura Parker    (515) 263-1658   3911 E 32nd St,  Des Moines, IA 50317

  Treow Lil (female)
      SIRE: Ch. Southports Black Orpheus (OFA fair)
       DAM: Hudsons Muggnificent Meghan

  Treow Syd (female)
      SIRE: Ch. Southports Black Orpheus (OFA fair)
       DAM: Hudsons Muggnificent Meghan

Marguerite Paduano    (619) 961-7883   9025 Central Rd,  Apple Valley, CA 92308

  Moonshadow Duke Beauregard (OFA good,OFEL) (male)
      SIRE: Moonshadow Prince Exidor
       DAM: Moonshadow Golden Amber

  Gussies Dream Of Success (OFEL) (female)
      SIRE: Ch. Southports Dream Warrior (OFA fair,CERF64)
       DAM: Gussie Gussie Bo Bussie

David Thompson

  SCA's Lord M Of Mystery Mtn (male)
      SIRE: King Titus Of Mystery Mtn
       DAM: High Deserts Queen Of The Nile (OFA good)

Theresa Terry

  Sweetco's Huggable Harley (female)
      SIRE: Moonshadow Duke Beauregard (OFA good,OFEL)
       DAM: Sweetshops Anging Besar (OFA good)

Sherry White  Sarabella1@aol.com
  (719) 495-8021  9660 Thoroughbred Ln,  Colorado Springs, CO 80908
  The Day The Lights Went On - Sara's Story

  Ch. Farpoint's Cassiopeia, CGC,TDI (female)
      SIRE: Ch. Meadowrun Dickens (OFA fair)
       DAM: Ch. A Shobiz Hannah Of Gaia (OFA good,OFEL,CERF44)

Margaret Hope

  Farpoint's Tristan The Fair (male)
      SIRE: Ch. Meadowrun Dickens (OFA fair)
       DAM: Ch. A Shobiz Hannah Of Gaia (OFA good,OFEL,CERF44)