# CD235a

Source: https://onco.cc/targets/cd235a/  
OnCo record `cd235a` (Target). Data CC BY-NC 4.0, attribute "Data from OnCo (onco.cc)"; commercial use needs a licence.

## TL;DR

CD235a marks red blood cells. In an immune test its job is the opposite of the others: it is used to find red cells so they can be excluded, because there are far too many of them to leave in.

## Summary

CD235a is glycophorin A, the main sialoglycoprotein of the red cell membrane and the carrier of the MN blood group antigens. It appears in whole-blood immune panels as a dump marker: red cells outnumber white cells by roughly a thousand to one, so they are identified by CD235a and excluded before anything else is counted. It is also used to identify erythroid precursors in marrow, which matters in myelodysplastic syndromes and erythroleukaemia.

## Fields

- Kind: Target
- Last checked: 2026-10-16
- Also known as: GYPA; glycophorin A
- Tags: immune-marker
- Symbol: GYPA
- Class: surface-antigen
- Biology: The major sialoglycoprotein of the red cell membrane and carrier of the MN blood group antigens.
- Where found: Red blood cells and their precursors

## Sources

- Wikipedia: https://en.wikipedia.org/wiki/Glycophorin_A
- HGNC:4702: https://www.genenames.org/data/gene-symbol-report/#!/hgnc_id/HGNC:4702

## Connected records

- targets: [PTPRC](https://onco.cc/targets/ptprc/)
- terms: [Anaemia](https://onco.cc/terms/anaemia/)

---
JSON: https://onco.cc/api/v1/entities/cd235a.json