which blood type is the rarest in the world?

The rarest blood type worldwide is Rhnull, often called "golden blood." Fewer than 50 confirmed cases exist globally, making it exceptionally scarce compared to common types like O-positive.

What Makes Rhnull Unique

Rhnull lacks all 61 known Rh antigens on red blood cells, first identified in 1961 in an Australian Aboriginal woman. This absence creates transfusion challenges but positions it as a universal donor for other rare Rh types. People with Rhnull often face hemolytic anemia due to its genetic recessive nature.

Rare Blood Types Ranked

Here's a comparison of the world's rarest blood types by prevalence:

Blood Type| Estimated Cases/Prevalence| Key Notes
---|---|---
Rhnull| <50 worldwide 19| No Rh antigens; "golden blood" for rare transfusions.
AB-negative| <1% population 35| Rarest of standard 8 ABO/Rh types in many regions.
Bombay (hh)| 4 per million; ~179 in India 3| Lacks H antigen; appears O but incompatible.

Why Rarity Varies by Region

AB-negative tops rarity lists in the US (1 in 167 people), while Rhnull transcends populations with cases in Europe, Japan, and Africa. Factors like genetics and isolation drive this—Rhnull requires inheriting recessive genes from both parents.

Health Implications and Donor Need

Those with Rhnull must receive only Rhnull blood, spurring global registries like those from the International Society of Blood Transfusion. Its value in medicine is immense, yet finding donors remains a lifelong challenge. Recent 2025-2026 reports confirm no new ultra-rare types have displaced it.

TL;DR: Rhnull reigns as the world's rarest blood type with under 50 known people—far rarer than AB-negative. Information gathered from public forums or data available on the internet and portrayed here.