Word decoding is significantly more heritable (.84) than mathematics (.60) and reading comprehension (.64) at age 12¶
Claim · All claims
Evidence · 1 study · associationalr3·q3
Currency · newest study 2012 · not yet checked against its sources · not reviewed by a person
Subclaims¶
Reading the evidence codes
q is the design tier, i the impact, n the sample, and the kind with its r
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This claim: no standardized effect is recorded in observations/ for it yet, so no benchmark reading is possible.
q3 i? Latent-factor heritability was significantly higher for word decoding (.84) than for mathematics (.60) and reading comprehension (.64). → Harlaar 2012
Evidence¶
Harlaar 2012¶
Harlaar, N., Kovas, Y., Dale, P. S., Petrill, S. A., & Plomin, R. (2012). Mathematics is differentially related to reading comprehension and word decoding: Evidence from a genetically-sensitive design. Journal of Educational Psychology, 104(3). https://doi.org/10.1037/a0027646
q3 · i? · associational · r3
Multivariate genetic model estimates of A, C, E proportions for latent factors in the 5162-pair twin sample. Word decoding showed "significantly higher heritability (.84)" than mathematics (.60) and reading comprehension (.64); shared and nonshared environmental effects were small but significant.
"There were few differences across measures, although word decoding showed significantly higher heritability (.84) compared with mathematics (.60) and reading comprehension (.64)."
Discussion¶
Related Claims¶
- A common genetic factor influences mathematics, word decoding, and reading comprehension, with substantial genetic overlap across all three domains — related
- At age 12, mathematics is more strongly correlated with reading comprehension than with word decoding at the phenotypic latent-factor level — related
- Reading comprehension retains genetic and nonshared environmental influences independent of both mathematics and word decoding — related
- Shared environmental influences on mathematics, word decoding, and reading comprehension are nearly identical across the three domains — related
- The genetic correlation between mathematics and reading comprehension (.76) is significantly higher than between mathematics and word decoding (.50) — related
- GPAΔ is strikingly highly heritable (85%), exceeding the heritability of achievement itself (67%) — related
Page metadata
| Field | Value |
|---|---|
type |
claim |
id |
word-decoding-more-heritable-than-math-and-comprehension |
title |
Word decoding is significantly more heritable (.84) than mathematics (.60) and reading comprehension (.64) at age 12 |
description |
Word decoding is significantly more heritable (.84) than mathematics (.60) and reading comprehension (.64) at age 12 |
status |
review |
evidence_strength |
moderate |
newest_evidence |
2012 |
generated |
by process:wiki-ingest on 2026-10-25 |
trust |
unverified — no one has confirmed this page's content |
sources |
1 — harlaar-2012 |
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