How is "Hoarding" encoded by the genome?
The popularity of shows like “Hoarders” has brought much-needed awareness to the problem of becoming overwhelmed with “stuff.” People who are hoarders often risk their health, their financial security, and the most important relationships in their lives in the struggle against extreme clutter. Many live in hazardous, unhealthy conditions that prevent positive interaction with family members and friends. But why do they do it? Are hoarders genetically compelled to surround themselves with piles of items that typically have little or no monetary value, or is there something else going on?
What Is the Difference Between Hoarding and Collecting?
The term “hoarding” is frequently used to describe the accumulation of an overabundance of items. For example, a person who enjoys knitting may joke that they are hoarding yarn because they have so many different types and colors of it stashed away for later use. While it is definitely possible to hoard craft supplies, hoarding is not a casual behavior or a habit to joke about. What is the difference between hoarding and collecting? In general, collectors are described as people who have a passion for gathering things such as antiques, arts, stamps, or anything of particular value. They generally organize and display their collections to showcase them for others to see. On the other hand, hoarding is characterized by difficulty discarding or parting with possessions that others often consider trash. This unusual behavior results in clutter that impacts one's day-to-day. In addition, hoarding can be a symptom of multiple neurological and psychiatric disorders.
What Is the Hoarding Gene?
Experts believe hoarding is caused by both environmental and genetic influences. About half of the people who hoard also have a family member who hoards. Studies suggest there is a link between a region on chromosome 14 and compulsive hoarding. This chromosomal variance is also linked to Alzheimer’s Disease.
What Is the Root Cause of Hoarding?
No single cause of hoarding has yet been identified. Like some other mental health conditions, it appears to be a combination of genetics, environment, and stressful life events. Some individuals may have inherited the genetic component for hoarding and experienced life in a hoarding household but do not exhibit hoarding behaviors themselves. Many experts believe it is the extra stressor of trauma that triggers those who are at risk to begin hoarding.
Exploring the Genetic Factors Behind the Hoarding Gene
A recent study showed that hoarding is highly prevalent and heritable, with genetic factors accounting for approximately 50% of its variance. However, very few studies have examined the genetic architecture of hoarding, and their results have been largely inconsistent. Researchers conducted a genome-wide association study for hoarding traits in a large cohort of Caucasian twins to examine the relationship between hoarding traits and specific genetic variants.
In this study, a sub-sample of 3,410 participants had been genotyped. All participants completed the Hoarding Rating Scale-Self-Report, a brief self-administered questionnaire that evaluates five items: clutter, difficulty discarding, excessive acquisition, distress, and impairment. Each item is scored on a numerical scale from 0 (none) to 8 (extreme), with a total score of 0 to 40. Although no SNPs demonstrated strong enough evidence for a statistically significant association at a genome-wide level of significance, two genomic loci on chromosome 6 and chromosome 5 showed suggestive evidence for an association with hoarding traits. The most significant single-nucleotide polymorphism (SNP) was rs3747767 which is located near the Leber Congenital Amaurosis 5 gene (LCA5) on chromosome 6. Participants with the minor allele (A) of the SNP showed an increased tendency for hoarding traits.
On the contrary, participants with the minor allele (G) of rs984926 on chromosome 5 showed a decreased tendency for hoarding traits. Importantly, all these association signals remained at the same level of significance after adjustment for OCD traits (scores on the Obsessive-Compulsive Inventory-Revised; OCI-R), suggesting a specific effect of these SNPs on hoarding traits over and above OCD symptoms.
The researchers addressed that the main limitations of this study were the predominance of females and the use of a self-reported measure to assess hoarding. However, the HRS-SR is a common and effective scale for measuring hoarding. Read more about the study here: https://pubmed.ncbi.nlm.nih.gov/21302353/
Did You Inherit Hoarding Genes?
Hoarding is a mental health concern that can affect people of any age or socioeconomic status. It is a method of coping with traumatic stress. People who were exposed to hoarding as children and those who inherited genetic hoarding traits are at greater risk for developing this disorder.
If you are concerned about your own hoarding behaviors, understanding your genotype may help. Upload your raw DNA data at Genomelink to find your status on this trait and many more.
Are you interested in learning more about your genetic tendency for hoarding? You can login to your Genomelink YOUR TRAITS to see this new genetic trait.
