sex hormones

thyroid

PDE8B

A Surprising Genetic Link to Thyroid Hormones (PDE8B)

Written by Aleksa Ristic, MS (Pharmacy) on August 21st, 2019

Did you know that genes are greatly responsible for thyroid hormone variations? One such gene is called PDE8B, and some of its variants correlate with hypothyroidism. Read on to learn more about this connection.

The Symptoms of Low Thyroid Hormones

Low thyroid hormones (hypothyroidism) are among the most common endocrine disorders. The typical symptoms include [R]:

Cold intolerance
Dry skin
Weight gain
Fatigue
Constipation

Did you know?

Levothyroxine for hypothyroidism is the second most prescribed drug in the US [R]
Around 20 million Americans have problems with their thyroid [R]

The Role of Genes

Is there a role for genetics in this “epidemic” of thyroid disorders? Given that genetic factors account for 50-90% of thyroid hormone variations, the answer is yes [R].

Genes control different stages of thyroid hormones production and release; certain variations in these genes correlate with hypothyroidism.

Low thyroid hormones manifest with cold intolerance, weight gain, and fatigue. Genes play an important role in thyroid hormone variations and related disorders.

Studies Point Their Finger to the PDE8B Gene

A study published in the American Journal of Human Genetics identified PDE8B variants—such as rs4704397—associated with low thyroid hormones [R].

In a study of almost 40,000 participants, this variant was associated with 18% higher rates of hypothyroidism. That said, the connection was weaker compared with some other variants analyzed in this study [R].

Other variants, such as rs2046045 and rs1382879, also correlated with low thyroid hormones in a couple of other clinical trials, especially in European descendants [R, R].

How It Works

The PDE8B gene encodes phosphodiesterase-8b, an enzyme that breaks down cAMP in your cells. cAMP is a messenger molecule for many vital functions, including the production of thyroid hormones [R, R].

TSH from the pituitary gland stimulates the thyroid to produce hormones by increasing cAMP. PDE8B and other phosphodiesterases destroy cAMP, reduce thyroid hormone production, and may thus impair thyroid function if they’re overactive [R].

With this reduction in thyroid hormones, TSH increases in an effort to restore order. Thus, high TSH indicates hypothyroidism. According to one clinical trial, there is an approximate increase of 0.13 μIU/ml in TSH for each ‘A’ allele at rs4704397 [R].

PDE8B encodes phosphodiesterase-8B, an enzyme that lowers thyroid hormones by destroying cAMP. Specific variants in this gene may increase its activity and correlate with hypothyroidism.

Your PDE8B Results for Hypothyroidism

SNP Summary

Primary SNP: PDE8B rs4704397 [R, R, R]

‘A’ = may be associated with higher TSH and hypothyroidism
‘G’ = normal TSH, not associated with hypothyroidism

Other Important SNPs:

PDE8B rs1382879 [R]

‘C’ = may be associated with higher TSH and hypothyroidism
‘T’ = normal TSH, not associated with hypothyroidism

PDE8B rs2046045 [R]

‘T’ = may be associated with higher TSH and hypothyroidism
‘G’ = normal TSH, not associated with hypothyroidism

SNP Table

variant	genotype	frequency	risk allele
rs4704397
rs1382879
rs2046045

Recommendations

Diet

Flavonoids such as luteolin, apigenin, and quercetin can naturally increase your cAMP levels. Make sure to consume a variety of good flavonoid sources: citrus fruits, berries, tea, etc. [R, R].

That said, certain flavonoids such as genistein from soy may worsen thyroid health in people with mild hypothyroidism and low iodine levels [R, R, R].

Methylxanthines (caffeine, theobromine, theophylline) are alkaloids found in tea, coffee, and cocoa. They can boost cAMP by inhibiting phosphodiesterase [R].

Supplements

Forskolin, a component from the Indian Coleus plant, can boost cAMP and potentially reduce the negative effects of your PDE8B variants [R].

By increasing cAMP, forskolin may stimulate the secretion of T4 from the thyroid, but clinical research hasn’t confirmed this effect [R, R].

Although flavonoids increase cAMP, excessive amounts may hinder the development of thyroid cells. Thus, you may want to avoid flavonoid supplements and stick with food sources instead [R, R].

Note: PDE8B is not sensitive to most of the above phosphodiesterase inhibitors, but they may help indirectly by increasing cAMP [R, R].

Forskolin is still in the investigational phase, and it’s not approved for the prevention or treatment of any medical condition.

Aleksa Ristic

MS (Pharmacy)

Aleksa received his MS in Pharmacy from the University of Belgrade, his master thesis focusing on protein sources in plant-based diets.

Aleksa is passionate about herbal pharmacy, nutrition, and functional medicine. He found a way to merge his two biggest passions—writing and health—and use them for noble purposes. His mission is to bridge the gap between science and everyday life, helping readers improve their health and feel better.

Disclaimer

The information on this website has not been evaluated by the Food & Drug Administration or any other official medical body. This information is presented for educational purposes only, and may not be used to diagnose or treat any illness or disease.

Also keep in mind that the “Risk Score” presented in this post is based only on a select number of SNPs, and therefore only represents a small portion of your total risk as an individual. Furthermore, these analyses are based primarily on associational studies, which do not necessarily imply causation. Finally, many other (non-genetic) factors can also play a significant role in the development of a disease or health condition — therefore, carrying any of the risk-associated genotypes discussed in this post does not necessarily mean you are at increased risk of developing a major health condition.

Always consult your doctor before acting on any information or recommendations discussed in this post — especially if you are pregnant, nursing, taking medication, or have been officially diagnosed with a medical condition.

More sex hormones blogs

A Gene That Activates Thyroid Hormones (DIO1) A Surprising Genetic Link to Thyroid Hormones (PDE8B) The Role of Genes in Thyroid Autoimmunity (PTPN22) Why Do Some People Have Better Thyroid Health? (FOXE1) The Gene Associated with "Hidden Hypothyroidism" (DIO2) What’s the Link Between This Gene and Thyroid Autoimmunity? (TSHR) Can This Gene Contribute To Autoimmune Thyroid Disorders? (STAT3) Is This Gene Connected To Autoimmunity And Thyroid Health? (SH2B3) How This Autoimmunity Gene Impacts Thyroid Health (CTLA4) How a Cell Structure Gene Impacts Thyroid Health (CAPZB)

More thyroid blogs

Content

The Symptoms of Low Thyroid Hormones Studies Point Their Finger to the PDE8B Gene Your PDE8B Results for Hypothyroidism

Unlock Personalized Results And So Much More!

Shipping Worldwide

30-Days Money-Back Guarantee*

HSA/FSA Eligible

Essential Bundle

SelfDecode DNA Kit

24/7 AI Health Coach
1250+ Comprehensive DNA Health Reports
Personalized Diet, Supplement, & Lifestyle Recommendations
Lifestyle Risk Assessments
Unlimited access to Labs Analyzer

$418

$376

Men's Health Month 10% Off

Essential

Bundle

Everything in essential
SelfDecode DNA Kit
Methylation Pathway
+130 Medical Reports
25+ Longevity Screener Risk Assessments

Odds ratios to evaluate your risk for 25+ medical conditions
10-year risk scores to prioritize health conditions
Lifetime risk scores to plan for long-term health

$667

$566

Men's Health Month 15% Off

Men's Health Month 30% Off

Ultimate Bundle

Everything in essential+
SelfDecode DNA Kit
Medication Check (PGx testing) for 50+ medications
40+ Family Planning (Carrier Status) Reports
Ancestry Percentages
Mitochondrial Ancestry

$894

$625

* SelfDecode DNA kits are non-refundable. If you choose to cancel your plan within 30 days you will not be refunded the cost of the kit.

We will never share your data

We follow HIPAA and GDPR policies

We have World-Class Encryption & Security

People Love Us

Rated 4.7/5 from 750+ reviews

People Trust Us

200,000+ users, 2,000+ doctors & 80+ businesses

SelfDecode is a personalized health report service, which enables users to obtain detailed information and reports based on their genome. SelfDecode strongly encourages those who use our service to consult and work with an experienced healthcare provider as our services are not to replace the relationship with a licensed doctor or regular medical screenings.

Policies

About

Support
Our Team
Affiliate Program
Privacy
Media