Mitochondrial DNA haplotype & response to placental restriction in sheep

This honours project in animal science aims to determine effects of mitochondrial DNA haplotype on extent and response to placental restriction in sheep.

Mitochondrial DNA (mtDNA) is maternally inherited and contains essential genes for cellular energy production, cell signalling and growth and development. Based on its major function in metabolism, mitochondrial DNA sequence variation has been associated with a range of metabolic parameters and disorders, including type 2 diabetes.

We have previously established a reference mitochondrial genome for sheep and subsequently demonstrated that domestic sheep show 5 major mtDNA variants or haplotypes that are not breed-specific (Hiendleder et al. 1998, J Mol Evol 47:441-8; Meadows et al. 2011, Heredity 106:700-6).

Individuals who grew poorly before birth are at increased risk of diabetes, partly because they have reduced insulin sensitivity compared to individuals who were of normal size at birth.

In this project, we are exploring whether sheep with different mtDNA haplotypes respond differently to experimentally induced placental and thus fetal growth restriction and whether these growth-restricted individuals differ in level of insulin sensitivity and glucose control.

This experiment is expected to provide basic non-mendelian genetic information for livestock production and human health alike.

Key methodology:

• You will extract total cellular DNA from frozen tissues and assign animals with a full phenotypic record (e.g., birthweight, postnatal growth performance, insulin sensitivity) to mtDNA haplotype groups by RFLP analyses and/or DNA sequencing.

• Haplotype information will be used to test for mtDNA effects on phenotype in statistical models using SPSS and/or SAS.

Scholarships:

• Choose this project and you will be eligible to apply for the JR Barker Scholarship.