Scientists have unearthed new genetic variants associated with Alzheimer’s disease, offering renewed hope for potential treatments and prevention strategies.
The study, led by researchers in the United States, has identified 17 genetic strains that may influence the risk of developing Alzheimer’s, a debilitating condition affecting over 55 million individuals worldwide. Utilizing whole genome sequencing, the researchers pinpointed these variants within five genomic regions, shedding light on novel avenues for combating the disease.
Alzheimer’s disease, the fifth leading cause of death among individuals aged 65 and older in the US, currently afflicts over six million Americans. Alarmingly, this figure is projected to nearly double by 2050, highlighting the urgent need for effective interventions.
Similarly, in the UK, more than 920,000 people grapple with Alzheimer’s and other forms of dementia, a number expected to soar to two million by 2050. Globally, cases are anticipated to triple, surpassing 150 million individuals affected by the disease.
Dr. Anita DeStefano, a professor of biostatistics at Boston University School of Public Health (BUSPH) and co-lead of the study, underscored the significance of whole genome sequencing in unraveling the complexities of Alzheimer’s disease.
“Whole genome sequence data interrogates every base pair in the human genome and can provide more information about which specific genetic change in a region may be contributing to Alzheimer’s disease risk or protection,” she explained.
The research, published in the Alzheimer’s Association’s journal, represents a departure from conventional studies focusing solely on common variants and regions. By delving into rare and crucial genes and variants, the study offers fresh insights into the genetic underpinnings of Alzheimer’s disease.
Drawing from data obtained through the Alzheimer’s Disease Sequencing Project (ADSP), established by the National Institutes of Health in 2012, the researchers conducted single variant association analyses and rare variant aggregation association tests. The ADSP dataset comprised over 95 million variants among 4,567 participants, both with and without the disease.
Among the 17 significant variants linked to Alzheimer’s disease, one, known as KAT8, stood out for its association with the disease in both single and rare variant analyses. Additionally, the researchers identified associations with several rare variants, notably TREM2 variants, shedding further light on the genetic architecture of Alzheimer’s disease.
Dr. Chlo Sarnowski, a researcher at UTHealth Houston School of Public Health and co-lead of the study, highlighted the study’s innovative methodology in assessing Alzheimer’s disease risk across diverse populations.
“By using whole genome sequencing in a diverse sample, we were able to not only identify novel genetic variants associated with Alzheimer’s disease risk in known genetic regions but also characterize whether the known and novel associations are shared across populations,” she elaborated.
Moreover, the study’s inclusion of participants from diverse genetic backgrounds, including White/European, Black/African-American, and Hispanic/Latino individuals, underscores its commitment to addressing health disparities in Alzheimer’s research.
Despite its groundbreaking findings, the study faced limitations due to its relatively small sample size, warranting further investigation into the identified genetic variants. Dr. Gina Peloso, a key contributor to the study, emphasized the ongoing efforts to expand research initiatives using whole genome sequencing with larger sample sizes within the ADSP.