# Rare coinheritance of hemoglobin vancleave with severe beta-thalassemia mutation in a patient with secondary erythrocytosis

## TL;DR

A rare hemoglobin variant combined with a severe beta-thalassemia mutation was found in a patient with high red blood cell count.

## Contribution

This is the first reported case of Hb Vancleave co-occurring with a severe beta-thalassemia mutation in Malaysia.

## Key findings

- Hb Vancleave and a beta-thalassemia mutation were identified in a patient with secondary erythrocytosis.
- Direct sequencing confirmed the rare hemoglobin variant and mutation combination.
- The case emphasizes the need for genetic sequencing in diagnosing beta-thalassemia in Malaysia.

## Abstract

Hemoglobin (Hb) Vancleave (NM_000518.5:c.431 A > T; dbSNP: rs33918338) is an extremely rare structural hemoglobin variant worldwide, and studies are limited. This report describes the case of a 16-year-old male patient who presented with secondary erythrocytosis. The diagnosis of Hb Vancleave, in combination with codon 41/42 (-TTCT) (NM_000518.5:c.126_129del; dbSNP: rs80356821), was confirmed by direct sequencing. This report highlights the importance of sequencing in the differential diagnosis of beta-thalassemia syndrome in Malaysia.