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Trait

Increased RBC distribution width

Red blood cell distribution width (RDW) is a simple parameter of the standard full blood count and a measure of heterogeneity in the size of circulating erythrocytes. It is provided by automated hematology analyzers and it reflects the range of the red cell size. It is calculated by dividing the standard deviation of erythrocyte volume by the mean corpuscular volume (MCV) and multiplied by 100 to convert to a percentage.

HPO HP:0031965

Summary

Also called
Increased red blood cell distribution width
Body system
Abnormality of blood and blood-forming tissues

Reference genomeGRCh38

Positions on gene and variant pages follow this choice, in this browser.

5 genes linked to Increased RBC distribution width

Changes in these genes cause rare conditions in which Increased RBC distribution width is seen. Most people with this trait have none of those conditions, and a gene on this list says nothing about anyone's own genome.

GeneHow often it is seenConditions
CBLIFcobalamin binding intrinsic factorAlwaysIn 1 condition
FAAP100FA core complex associated protein 100AlwaysIn 1 condition
GATA1GATA binding protein 1AlwaysIn 1 condition
GFI1Bgrowth factor independent 1B transcriptional repressorAlwaysIn 1 condition
KLF1KLF transcription factor 1AlwaysIn 1 condition

How often is among people with one of the gene's conditions, the most often across them, as the Human Phenotype Ontology records it. These pages describe traits and the research behind them; they are not a diagnosis, and a doctor or genetic counsellor is the person to ask about symptoms.

Broader traits

Abnormal erythrocyte morphology

Where this comes from

  • The Human Phenotype Ontology, release 2026-09-01: the trait, its names, its definition and the genes linked to it. Find out more at hpo.jax.org.
  • Data release 2026.10.16-c6eea6bf.

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