The Claim

The DIO1 p.Asn94Lys and p.Met201Ile variants reduce enzyme affinity for thyroxine, resulting in a two- to threefold increase in Michaelis constant (Km) and slower enzymatic velocity, as demonstrated by in vitro kinetic assays in transfected HEK293 cells.

Source: Human Type 1 Iodothyronine Deiodinase (DIO1) Mutations Cause Abnormal Thyroid Hormone Metabolism

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
49score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

Two specific genetic changes in the DIO1 enzyme reduce its binding to thyroxine, leading to a two- to threefold higher Michaelis constant and reduced reaction speed in laboratory cell studies.

See the scientific wording

The DIO1 p.Asn94Lys and p.Met201Ile variants reduce enzyme affinity for thyroxine, resulting in a two- to threefold increase in Michaelis constant (Km) and slower enzymatic velocity, as demonstrated by in vitro kinetic assays in transfected HEK293 cells.

Why this might work

Changes in the DIO1 enzyme's structure make it harder for the enzyme to grab thyroxine, so it processes the hormone more slowly. This causes less active thyroid hormone to be made and more inactive hormone to build up in the blood.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Human Type 1 Iodothyronine Deiodinase (DIO1) Mutations Cause Abnormal Thyroid Hormone Metabolism

    Scientists found that two specific changes in a thyroid gene make the enzyme work much slower because it can't grab its fuel (thyroxine) as well — just like the claim said. They tested this directly in human cells in the lab.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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