Download to - Stud Game Breeders

PROF BETTINE VAN VUUREN
Department of Zoology
Tel: 011 559 2457
[email protected]
Overview
• Different types of DNA
• And what we can gather from these
• Correct markers for the questions asked
• Current state of genetic testing in wildlife
Some information about genetics
Mitochondrial DNA
• Maternally inherited
• No contribution from father
• “Pure” – will not change over time
Cell
Some information about genetics
Mitochondrial DNA
• Maternally inherited
• No contribution from father
• “Pure” – will not change over time
Nuclear DNA
Cell
• Bi-parentally inherited
• Contribution from father and mother
• Will reflect admixture, i.e. changes over time
Implications of the two types of DNA
• Nuclear data show contribution from mother and father
• Will show admixture, and probability of belonging to specific groups
Nuclear DNA
M
X
F
Mitochondrial DNA
=
50% : 50%
M
X
F
=
16% membership
to each group
Remain pure
Coding and non-coding genes
Coding and non-coding genes
Coding and non-coding genes
Coding DNA
- Code for genes that translate into physical characteristics
- Coat colour, horn length, ect
- Slow mode of change
Coding and non-coding genes
Non-coding DNA
- Function unknown
- Faster rate of change (no constraint on change)
Coding DNA
- Code for genes that translate into physical characteristics
- Coat colour, horn length, ect
- Slow mode of change
Coding and non-coding genes
Focus today
Future focus
-Non-coding
-Coding
Different kinds of DNA for different kinds of questions
• The one is not better than the other – it is simply a matter of the
question that you ask…..
• Coding DNA (requires one to identify the correct gene[s])
• Information regarding physical characteristics
• ¿What is the potential of my animal regarding horn length?
• ¿What is the potential of my animal regarding % fat in milk?
• Non-coding DNA
•
•
•
•
Information regarding historical origin and movement in animals
¿Is genetic variation geographically structured in species?
¿To what extent do animals move around?
¿Was my buffalo fathered by Horison or my sable by Charlie?
Current state of genetic testing
Types of questions answered today
• ¿Is genetic variation geographically structured in specific species?
• Mitochondrial DNA and non-coding nuclear DNA
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
Current state of genetic testing
•
¿Is genetic variation geographically structured in specific species?
• Mitochondrial DNA and non-coding nuclear DNA
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
• ¿What is the historical origin of my specific animal?
• Mitochondrial DNA and non-coding nuclear DNA
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
Current state of genetic testing
•
•
•
¿Is genetic variation geographically structured in specific species?
• Mitochondrial DNA and non-coding nuclear DNA
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
¿What is the historical origin of my specific animal?
• Mitochondrial DNA and non-coding nuclear DNA
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
¿Forensic identification and paternity?
• Non-coding nuclear DNA (microsatellites)
• Not mitochondrial DNA because it is not variable enough
• NOT coding nuclear DNA because it is under evolutionary and environmental
constraints
Questions answered today
•
•
•
•
Geographic origin
Pure or hybrid
Forensic identification
Colour variation – more successful in some species than others
Proposed future trends
• Potential of animals regarding physical characteristic
• What genes do my animal carry and pass on to next generation
• Outcome = “….Informed selection….”
Geographic structure
• It has always been accepted that species are geographically
structured
• Phenotypic differences were recognized and translated into
subspecies descriptions
• These often followed geopolitical borders (not correct), geological
features (often correct) or other landscape features
• Accurate baseline data
Conservation strategies based on these are, at best, inefficient, and
may decrease evolutionary potential of species
Anthony Bannister
To summarize……
• Different kinds of DNA
• Mitochondrial and nuclear
• Coding and non-coding
• Important to understand the kinds of questions asked and the kinds
of markers used
• Current tests focus on:
•
•
•
•
•
Geographic origin
Pure herds
Forensic identification
Paternity
~ Colour variation
Conservation management
My message to you……
1. Understand the information available to you
• This is true for all types of information including genetic, ecology, behavior ect
2. Remain informed
• Google
• Ask people that work in the field
3. Do not believe everything you read or what people tell you…
• Do your own homework