The French observatory on genetic defect: an assessment...
Transcript of The French observatory on genetic defect: an assessment...
![Page 1: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/1.jpg)
The French observatory on genetic defect: an assessment after 15 years of operation
Coralie DANCHIN-BURGE, Institut de l’Elevage, France Cécile GROHS, INRA GABI, France
![Page 2: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/2.jpg)
Titre du diaporama & date de présentation
Genetics defects in cattle Ne, the Effective Population Size (=diversity) in cattle is very low due to high selection pressure
Examples with French selected populations: - Ne Holstein = 96 - Ne Charolais = 704
Inbreeding rate = homozygous animals ⇒Several crisis due to genetic defects since the 90s
(BLAD, CVM, brachyspina, weaver syndrom etc.) ⇒Need to implement a specific monitoring on the
emergence of genetic defects 2
![Page 3: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/3.jpg)
Titre du diaporama & date de présentation
Welfare and genetic defect
![Page 4: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/4.jpg)
Titre du diaporama & date de présentation
4
Welfare and genetic defect
![Page 5: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/5.jpg)
Titre du diaporama & date de présentation
Monitoring the emergence of genetic defects
French national observatory on genetic defects created in 2002 - ONAB
• Monitoring of genetic defects emergence: simple statistics based on a declaration form (paper, web site)
• Triggers scientific research when an emergence is detected in field
• Communication on genetic defects: newsletter, seminars, website…
5 Dwarfism in Charolais
![Page 6: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/6.jpg)
Titre du diaporama & date de présentation
6
Our goal: To be effective, despite a low rate of reporting
=> Using a participative science approach
Limiting factors: - Restricted number of cases reported - Inaccurate phenotypic descriptions which can lead to a
wrong diagnosis of the situation
![Page 7: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/7.jpg)
Titre du diaporama & date de présentation
Targeted information about a potential emergency to a wider
network : breeders’ association, selection companies, veterinarian
(incl. schools)
“Devoted to the cause” Core of proactive people - inseminator,
veterinarian etc. - Systematic report of any defects
- Early warning of emergences
7
ONAB
![Page 8: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/8.jpg)
Titre du diaporama & date de présentation
First example: overbent fetlocks in the Montbeliard breed
8
![Page 9: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/9.jpg)
Titre du diaporama & date de présentation
First example: overbent fetlocks in the Montbeliard breed
9
• AI center • Breed’s
organization
« Watchmen »
• Triggers an alert • Writing of a
specific overbent fetlock form
ONAB • Specific
work with a vet school
Global network
Numerous reports (declaration forms) overbent fetlocks
Information letter + website
• Specific forms •Blood/ear samples
On going research
![Page 10: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/10.jpg)
Titre du diaporama & date de présentation
Second example: “no hair or teeth” in the Charolais breed
10
![Page 11: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/11.jpg)
Titre du diaporama & date de présentation
Second example: “no hair or teeth” in the Charolais breed Anhidrotic Ectodermal Dysplasia
11
• First alerts: Participative website restricted to vets only, “vetofocus” (2013) – however the ONAB is not
contacted
A veterinarian specialized in cattle dermatological diseases contacts the ONAB at the same time
• First specific work by the ONAB: Anhidrotic Ectodermal Dysplasia= a well known genetic defect. But what triggers our
attention: both males and females have the disease (in the literature: only males)
Analysis of the pedigree structure: a mutual ancestor is found => recessive allele
=> Specific calls for new cases with biological samples
![Page 12: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/12.jpg)
Titre du diaporama & date de présentation
Second example: “no hair or teeth” in the Charolais breed
12
• Samples genotyping with a 50K SNP chip (< 10 animals) => Large common haplotype found in a gene responsible for hair growth => New mutation, that starts to spread in the Charolais population (0.5% of the population is carrier, mutation in AI and natural service lines) => Development of a specific genotype test (now combined with other genetic defects such as ataxia and progressive blindness in Charolais)
![Page 13: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/13.jpg)
Titre du diaporama & date de présentation
Perspectives for monitoring the emergence of genetic defects
• Monitoring of genetic defects emergence • Triggers scientific research (including fine phenotyping) • Communication: newsletters, website, seminars…
ONAB - French national observatory
on genetic defects
• Bulls genetic evaluations on vitality • Mortality observatory (bases on calves exit dates)
National genetic database
• Detection of haplotypes associated with prenatal death • Reverse genetic approach Genomic data
13
2002
2016
![Page 14: The French observatory on genetic defect: an assessment ...eaap.org/Annual_Meeting/2016_belfast/S46_04_Danchin.pdf · Inbreeding rate ... •Mortality observatory (bases on calves](https://reader033.fdocuments.us/reader033/viewer/2022050312/5f73dd936d211103a377841a/html5/thumbnails/14.jpg)
Titre du diaporama & date de présentation
Acknowledgment
14
And all the ONAB partners: