Genetic Variance factors are in-comprehensive across cultures for complex genetic disorders.

 Earlier in the semester, Dr.  Mary Makarious discussed her research on the genetic variability of diagnosing and treating Parkinson's disease. While there is much research surrounding the common variants of genetic causes for PD, they often represent a Eurocentric test group. Studies focusing on less represented populations have highlighted the need for a more representative sample, as it has been found that there are risk allele variations in the genetic component of PD that varies depending on ethnic background. More information on varying genetic factors will help provide equity of treatment for PD and related disorders by allowing researchers to better locate previously unavailable therapeutic targets along with creating a new population for clinical trials. 

Another complex genetic disorder experienced by millions worldwide is Alzheimer's disease. It is estimated to affect over 40 million people, and seen in 30% of individuals over the age of 80. Researchers found that 60-80% of the risk for Alzheimer's disease comes from heritable genetic factors and allele variations on over 70 different loci. This is an extremely high percentage when compared to Parkinson's 25% inheritable risk. Despite this research indicating the prevalent impact of variations at these loci, the progress of targeting the specific allele variations that create these risk factors is extremely limited. Much like research pertaining to the genetic risk of Parkinson’s, the data is coming primarily from non-hispanic North Americans and Europeans. This is extremely limiting to the overall generalizability of the diagnosis as well as treatment. Studies in less represented regions such as Africa, India, Asia, and South America have shown that variants are often specific to country or region indicating that the data currently available is not comprehensive and overall ineffective at both diagnosing and treating. There have been many initiates to combat this, such as GP2 for Parkinson's, but through papers such as this, we can see that we have a long way to go when it comes to fully understanding genetic factors and variance as an underlying cause for diseases such as Alzheimers.

References:

Blauwendraat, C., Noyce, A. J., Mata, I. F., Screven, L. A., Solle, J., Dumanis, S. B., ... & Singleton, A. B. (2025). Tackling a disease on a global scale, the Global Parkinson’s Genetics Program, GP2: A new generation of opportunities. The American Journal of Human Genetics, 112(9), 1988-2000

Reitz, C., Pericak-Vance, M. A., Foroud, T., & Mayeux, R. (2023). A global view of the genetic basis of Alzheimer disease. Nature Reviews Neurology, 19(5), 261-277.