What is rs1667255 (TTR) nd Why Does the Nutrient Zoomer Test for It?

Transthyretin gene variant

rs1667255 is a single nucleotide variant in the TTR gene, which encodes transthyretin, a blood transport protein for thyroid hormones and retinol-binding protein–vitamin A complexes. Variation at this site can affect protein expression or stability and helps explain individual differences in nutrient transport and metabolism when viewed with the Nutrient Zoomer.

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rs1667255 (TTR)

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About rs1667255 (TTR)

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About rs1667255 (TTR)

Overview and History

rs1667255 is a single nucleotide polymorphism (SNP) located in the TTR gene, which encodes transthyretin (historically called prealbumin). Transthyretin is a circulating tetrameric protein that carries thyroid hormones and the retinol-binding protein–vitamin A complex, contributing to nutrient distribution and endocrine-bound transport in blood. Genetic changes in TTR can alter how much transthyretin is produced or how stable the tetramer is, which in turn can influence protein turnover and carrier function. Because transthyretin interacts directly with vitamin A transport and thyroid-hormone carriage, variation in TTR has clinical research relevance for interpreting nutrient status and protein-related metabolic patterns.

Interpreting Highs and Lows

Different rs1667255 alleles have been associated with changes in transthyretin expression or stability. Lower transthyretin levels or genotypes linked to reduced expression may be associated with reduced carrier capacity for vitamin A and thyroid hormones and can coincide with low-protein states or systemic inflammation. Higher levels or genotypes associated with preserved or increased expression may suggest greater transport capacity, but genotype effects should be interpreted alongside measured retinol, thyroid markers, protein status, and the full Nutrient Zoomer profile for meaningful context.

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Including rs1667255 in the Nutrient Zoomer links inherited variation in the transthyretin gene to measured nutrient and protein markers. The marker evaluates potential changes in carrier protein expression or stability that influence vitamin A and thyroid-hormone distribution, helping providers interpret lab patterns and tailor nutrition strategies to individual biochemistry.

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rs1667255 (TTR) FAQs

What is rs1667255 (TTR) and why is it important?

rs1667255 is a specific DNA variant in the gene for transthyretin, the blood protein that helps carry thyroid hormones and vitamin A bound to retinol-binding protein. It matters because genetic differences at this site can change how much functional carrier protein is present or how stable it is. That variation can influence how nutrients and hormones are distributed and helps explain differences in lab patterns among individuals.

What does it mean if my rs1667255 (TTR) levels are low?

When rs1667255 is associated with lower transthyretin expression, it may point to reduced carrier capacity for vitamin A and thyroid hormones and can coincide with low-protein states or inflammatory signals. Low genetic-linked expression is an association, not a diagnosis, and is most informative when considered with measured retinol, thyroid-related tests, and overall Nutrient Zoomer results.

What does it mean if my rs1667255 (TTR) levels are high?

Alleles linked with higher transthyretin expression may indicate preserved or greater transport capacity for thyroid hormones and vitamin A. Elevated expression by genotype is an association that requires correlation with blood nutrient measures, thyroid markers, and clinical context to understand its functional significance.

Why is this biomarker included in the Nutrient Zoomer?

rs1667255 helps connect inherited differences in a key transport protein to measured nutrient and protein levels. That genetic insight refines interpretation of vitamin A, thyroid-related markers, and protein-nutrition patterns, supporting more precise, individualized assessment of nutrient handling.

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