Boost Your Intelligence by Increasing Myelination (ENPP6)

You probably already know that neurons are the main type of cell responsible for storing and processing information in your brain, and that they communicate with each other primarily by passing electrical signals between them.

Although neurons can conduct electrical signals on their own, they actually work much more efficiently when they are covered by an extra layer of myelin. Myelin is a fatty (lipid) coating that greatly increases the speed of the electrical signals that neurons use to communicate with each other [R].

Myelin also forms the so-called “white matter”, the parts of the brain that connect the different areas of the cortex to each other so that they can all work together effectively [R, R].

However, neurons cannot develop myelin all by themselves. Instead, they are given myelin (myelinated) by a completely different type of brain cell, called oligodendrocytes [R].

Even though these cells don’t play a “direct” role in neural processing, oligodendrocytes nevertheless play a key supporting role by helping your neurons communicate with each other as effectively as possible [R, R].

An oligodendrocyte cell (orange) providing myelin coverings to the axons of neurons (blue). Image source: [R]

In order to work effectively, your neurons need to be coated with a substance called myelin. Myelin is produced by a specific type of brain cell called oligodendrocytes.

The amount of myelination a person has is also affected by the genes they carry [R].

Additionally, the total amount of myelin a person has in their brain is one of the major genetic factors that has been associated with cognitive performance (more is better) [R, R, R, R].

Conversely, having low levels of the various genes responsible for creating myelin is associated with cognitive deficits (such as reduced processing speed and impaired learning and memory) [R, R, R].

The amount of myelin in your brain is influenced by your genes – and the more myelin you have, the better your overall cognitive ability!

The ENPP6 gene codes for an enzyme, also called ENPP6 (ecto-nucleotide pyrophosphatase/ phosphodiesterase 6) [R].

This gene is important because it supports brain myelination in several different ways.

For example, the ENPP6 enzyme plays a key role in enabling your brain to grow new oligodendrocytes, and is required for them to develop properly [R, R].

ENPP6 is also highly expressed in myelin itself, suggesting that this enzyme also plays a direct role in the processes that allow oligodendrocytes to create myelin in the first place [R].

The significant role this gene plays in overall brain myelination is probably why SNPs in this gene have been linked to general intelligence (IQ) in humans [R]. SNPs in the ENPP6 gene have also been associated with more specific individual cognitive functions, such as fluid intelligence, processing speed, and learning and memory [R, R, R].

The ENPP6 gene affects your cognitive ability by determining the overall level of myelination throughout your brain.

Below you can see your genotype for rs4241784, a SNP in the ENPP6 gene that has been found to have a significant influence on several different aspects of cognitive ability:

The two possible alleles for this SNP are ‘T’ and ‘G’. In general, it is better to have the ‘T’ allele, which is associated with enhanced cognitive ability due to increased myelination throughout the brain [R, R].

Conversely, carriers of the ‘G’ allele are at a relative disadvantage when it comes to cognitive ability. This is probably because their ENPP6 gene is less active, which leads to lower levels of myelination.

For example, reducing or blocking the ENPP6 gene in mice impairs their brain’s ability to create new oligodendrocytes, which leads to reduced overall levels of myelination in their brains (hypomyelination) [R, R].

Because they have less overall myelination in their brains, mice with reduced ENPP6 gene activity also show significant cognitive deficits when it comes to their ability to learn new skills and acquire new memories [R, R].

The results of these animal studies are highly consistent with similar findings in humans, where people with less myelination show similar reductions in cognitive ability [R].

Carriers of the ‘T’ allele for rs4241784 show enhanced cognitive ability, whereas carriers of the ‘G’ allele show relatively poorer cognitive ability.