Hemophilia / Blood Disease / Von Willebrand disease

Hemophilia B - The disease

Hemophilia B is a major inherited bleeding disorders in the breed Rhodesian Ridgback.

The disease is a deficiency or reduced activity of factor IX due to the key role in the clotting cascade has a. Depending on the severity of the factor IX deficiency causes a mild to severe bleeding.  Signs of hemophilia, larger hematomas, epistaxis, skin, muscle and joint bleeding. Gravity gradients after major injury or surgery can be fatal without treatment or prophylaxis.


Hemophilia B - The mutation and the inheritance

A missense mutation in exon 7 of factor IX was able to Laboklin in cooperation with Prof. Dr. Mischke (Veterinary Medicine) for the lack of active factor IX protein be identified as the cause.

Hemophilia B is an X-linked (sex-linked) recessive.This means that a male can already ill when he affected X-chromosome carries a. The mutated gene is transmitted through the mother.  Often females are healthy carriers (female carriers) of a mutated X chromosome. 50% of male offspring Konduktorin a disease, while 50% of the female descendants of healthy female carriers themselves.  Females become ill when they each affected gene from father and mother get one. In this case, both father and mother have the mutated gene (mating of males with hemophilia-Konduktorin).


There are three genotypes:

1. Female genotype N (X) / N (X), male genotype N (X) / Y (homozygous normal): This dog is genetically healthy and the symptoms are not triggered by the mutation characteristics. To the descendants of the intact gene is only passed on.

2.  Female genotype N (X) / FIX (X) (heterozygous winner): This bitch with a copy of the mutated gene. It has a low risk of hemophilia B (factor IX decreased activity) may become ill, the mutation probability of 50% of their offspring to share with.


3.male genotype FIX (X) / Y (hemizygous affected): Because of the X-linked inheritance with a bitch two copies of the mutated gene, while a male with a copy of the mutated gene bears. Both have high risk of hemophilia B with an extremely ill.  The affected allele is a bitch to 100% of their descendants passed on.One male inherited the affected allele with a probability of 50%.



Hemophilia B - DNA test

The defect in the underlying mutation can now DNA test proved to be an agent. The DNA analysis is independent of the age of the animal can and can already be carried out puppies. It is not only a distinction between affected and free animals possible with the help of genetic testing may also clinically healthy carriers are identified, what is of great importance for breeding.
To test to provide maximum security, is the examination of each sample in two independent assays.
For the tests, we need 1 ml EDTA-blood or a swab.Swab kits and instructions for the swab-sampling them free of charge at Laboklin.The result is about 3-5 working days after receipt of sample before.


For more information please contact at

Dr. Petra Kühnlein or Dr. Ines Langbein-Detsch,

LABOKLIN GmbH und Co. KG, Steubenstraße 4, 

D-97688 Bad Kissingen unter Tel. 0971 /72020 

oder Fax: 0971 / 7202995 oder Email labogen@laboklin.de " 

  Prepared by the Rhodesian Ridgeback breeders:
Mashambani

& Mhangura