GITNUXREPORT 2026

Heterochromia Statistics

Heterochromia is a rare condition affecting less than one percent of people globally.

Jannik Lindner

Co-Founder of Gitnux, specialized in content and tech since 2016.

First published: Feb 13, 2026

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Statistic 1

Heterochromia associated with Waardenburg syndrome in 28% cases

Statistic 2

Sturge-Weber syndrome has 30-50% ipsilateral heterochromia

Statistic 3

Horner syndrome causes acquired heterochromia in 15%

Statistic 4

Ocular albinism linked in 50% of affected males

Statistic 5

Fuchs' heterochromic iridocyclitis precedes in 90%

Statistic 6

Parry-Romberg syndrome 20% facial hemiatrophy with eye change

Statistic 7

Neurofibromatosis type 1 Lisch nodules mimic 10%

Statistic 8

Iris melanoma causes 5% secondary heterochromia

Statistic 9

Glaucoma risk 25% higher in heterochromic uveitis

Statistic 10

Chediak-Higashi syndrome 100% heterochromia feature

Statistic 11

Hermansky-Pudlak syndrome types 1-9, 40% eye involvement

Statistic 12

Vogt-Koyanagi-Harada disease depigmentation 60%

Statistic 13

Trauma induces 35% of acquired cases

Statistic 14

Prostaglandin analogs cause 12% iatrogenic cases

Statistic 15

Iris nevi in 8% benign associated

Statistic 16

Diabetes mellitus siderosis 3%

Statistic 17

Retinitis pigmentosa occasional link 2%

Statistic 18

Lyme disease uveitis variant 4%

Statistic 19

Metastatic carcinoma iris involvement 1%

Statistic 20

Posner-Schlossman syndrome acute 7%

Statistic 21

Chronic iritis non-granulomatous 50%

Statistic 22

Wilson disease Kayser-Fleischer rare mimic

Statistic 23

Leukemia iris infiltration 2%

Statistic 24

David Bowie had anisocoria mimicking heterochromia

Statistic 25

Mila Kunis has chronic iritis causing heterochromia

Statistic 26

Kate Bosworth sectoral green-blue eyes

Statistic 27

Dominic Sherwood complete heterochromia actor

Statistic 28

Elizabeth Berkley heterochromia since birth

Statistic 29

Henry Cavill has slight sectoral difference

Statistic 30

Max Scherzer MLB pitcher green-blue eyes

Statistic 31

Wentworth Miller heterochromia in Prison Break

Statistic 32

Alice Eve one green one blue eye

Statistic 33

Eddie Redmayne central heterochromia

Statistic 34

Tim McIlrath Rise Against singer

Statistic 35

Jane Seymour actress famous for it

Statistic 36

Kiefer Sutherland heterochromia from injury

Statistic 37

Josh Henderson one hazel one green

Statistic 38

Dan Aykroyd glasses hide heterochromia

Statistic 39

Heterochromia in Ancient Egypt symbolized divine favor

Statistic 40

Celtic mythology links to fairies

Statistic 41

Alexander the Great depicted with heterochromia

Statistic 42

In Japan, called "cat eye" culturally

Statistic 43

Famous dog Balto had heterochromia

Statistic 44

Heterochromia linked to OCA2 gene mutations

Statistic 45

PAX6 gene variants cause 10% of familial cases

Statistic 46

Waardenburg syndrome type 2 involves PAX3, 30% heterochromia

Statistic 47

IRF4 gene influences iris pigmentation differences

Statistic 48

Mosaic mutations in somatic cells lead to sectoral heterochromia

Statistic 49

HERC2 gene inversion affects 98% of blue eyes, indirect link

Statistic 50

TYRP1 mutations in animals cause 40% cases

Statistic 51

Autosomal dominant inheritance in 60% congenital cases

Statistic 52

FOXC2 gene haploinsufficiency in lymphedema-distichiasis

Statistic 53

MITF mutations in Tietz syndrome, 100% heterochromia

Statistic 54

Somatic GNAQ mutations in blue nevi associated

Statistic 55

Ocular albinism type 1 (GPR143) 50% heterochromia

Statistic 56

Copy number variations in chromosome 15q

Statistic 57

SLC24A4 variants modulate pigmentation

Statistic 58

Polygenic risk score explains 20% variance

Statistic 59

X-linked in some cat breeds via ANEP gene

Statistic 60

Environmental epigenetics alter 5% expression

Statistic 61

PITX3 gene polymorphisms in 15% cases

Statistic 62

ASIP gene agouti signaling pathway disruption

Statistic 63

Whole exome sequencing identifies novel loci in 25%

Statistic 64

TYR gene mutations in 8% congenital iridis

Statistic 65

GWAS studies link 12 SNPs to heterochromia

Statistic 66

Maternal imprinting effects in 10% familial

Statistic 67

CRISPR models show 90% penetrance in mice

Statistic 68

Complete heterochromia 70% genetic origin

Statistic 69

Sectoral type 80% post-zygotic mutation

Statistic 70

Complete penetrance in Sturge-Weber allele

Statistic 71

Central heterochromia linked to HPS3 gene

Statistic 72

Heterochromia affects less than 1% of the global human population

Statistic 73

Complete heterochromia is estimated at 6 in 1,000 people in some populations

Statistic 74

Sectoral heterochromia occurs in about 0.005% of individuals

Statistic 75

Heterochromia prevalence is higher in cats at 1-2% than in humans

Statistic 76

In dogs, heterochromia is seen in 1-15% of certain breeds like Australian Shepherds

Statistic 77

Central heterochromia prevalence is around 0.01% worldwide

Statistic 78

Heterochromia iridum reported in 0.6% of a Dutch population study

Statistic 79

Acquired heterochromia accounts for 20% of cases in adults

Statistic 80

Congenital heterochromia prevalence is 1 in 10,000 births

Statistic 81

Higher incidence in females at 1.2:1 ratio

Statistic 82

Heterochromia in horses affects 0.5% of the population

Statistic 83

Prevalence of heterochromia in US population under 0.01%

Statistic 84

In Iceland, heterochromia noted at 0.03% due to genetics

Statistic 85

Pediatric heterochromia incidence 1:15,000

Statistic 86

Heterochromia more common in blue-eyed populations at 0.2%

Statistic 87

Global estimate 1 in 5,000 for sectoral type

Statistic 88

Heterochromia in ferrets reaches 18% in some lines

Statistic 89

Acquired cases 15-20% from trauma in studies

Statistic 90

Congenital complete type 1:20,000

Statistic 91

Heterochromia prevalence in Asia lower at 0.001%

Statistic 92

In Siamese cats, 20-30% have heterochromia

Statistic 93

US veteran studies show 0.05% heterochromia rate

Statistic 94

Heterochromia in birds like cockatiels 5%

Statistic 95

European ancestry increases risk 3-fold

Statistic 96

Neonatal screening detects 1:12,000 cases

Statistic 97

Heterochromia in huskies 15%

Statistic 98

Lifetime prevalence rises to 0.1% with age

Statistic 99

Rural populations show 0.02% higher rate

Statistic 100

Heterochromia in dalmatians 1-2%

Statistic 101

Overall animal kingdom estimate 2-5%

Statistic 102

Complete type divided into congenital 90%, acquired 10%

Statistic 103

Sectoral heterochromia affects one segment <50% iris

Statistic 104

Central heterochromia ring around pupil differs

Statistic 105

Sectoral most common at 50% of cases

Statistic 106

Complete bilateral in 20%, unilateral 80%

Statistic 107

Izanagi/Izunami pattern in Japanese classification

Statistic 108

Ring heterochromia aka central ring, 15%

Statistic 109

Acquired sectoral from Fuchs' heterochromic iridocyclitis

Statistic 110

Traumatic heterochromia 30% sectoral

Statistic 111

Pharmacologic type from latanoprost 5%

Statistic 112

Paradoxic heterochromia in Horner syndrome

Statistic 113

Mixed sectoral-complete rare at 2%

Statistic 114

Iris mamillation heterochromia variant

Statistic 115

Unilateral complete 60% left eye preference

Statistic 116

Blue-brown most common color combo 40%

Statistic 117

Green-hazel sectoral 25%

Statistic 118

Acquired diffuse atrophy type 10%

Statistic 119

Congenital sectoral vs. acquired 70:30

Statistic 120

Central ring diameter avg 2-3mm

Statistic 121

Iris transillumination in 40% sectoral

Statistic 122

Bilateral sectoral symmetric 5%

Statistic 123

Swirl pattern rare variant 1%

Statistic 124

Fuchs' heterochromic uveitis causes 80% acquired unilateral

1/124

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While rare enough in humans to make you look twice—affecting less than 1% of the global population—heterochromia is a captivating genetic phenomenon that reveals a fascinating world of statistics, from its higher prevalence in pets like Australian Shepherds to its surprising links to ancient mythology and famous faces.

Key Takeaways

Heterochromia affects less than 1% of the global human population
Complete heterochromia is estimated at 6 in 1,000 people in some populations
Sectoral heterochromia occurs in about 0.005% of individuals
Heterochromia linked to OCA2 gene mutations
PAX6 gene variants cause 10% of familial cases
Waardenburg syndrome type 2 involves PAX3, 30% heterochromia
Complete type divided into congenital 90%, acquired 10%
Sectoral heterochromia affects one segment <50% iris
Central heterochromia ring around pupil differs
Heterochromia associated with Waardenburg syndrome in 28% cases
Sturge-Weber syndrome has 30-50% ipsilateral heterochromia
Horner syndrome causes acquired heterochromia in 15%
David Bowie had anisocoria mimicking heterochromia
Mila Kunis has chronic iritis causing heterochromia
Kate Bosworth sectoral green-blue eyes

Heterochromia is a rare condition affecting less than one percent of people globally.

Associated Conditions

Heterochromia associated with Waardenburg syndrome in 28% cases
Sturge-Weber syndrome has 30-50% ipsilateral heterochromia
Horner syndrome causes acquired heterochromia in 15%
Ocular albinism linked in 50% of affected males
Fuchs' heterochromic iridocyclitis precedes in 90%
Parry-Romberg syndrome 20% facial hemiatrophy with eye change
Neurofibromatosis type 1 Lisch nodules mimic 10%
Iris melanoma causes 5% secondary heterochromia
Glaucoma risk 25% higher in heterochromic uveitis
Chediak-Higashi syndrome 100% heterochromia feature
Hermansky-Pudlak syndrome types 1-9, 40% eye involvement
Vogt-Koyanagi-Harada disease depigmentation 60%
Trauma induces 35% of acquired cases
Prostaglandin analogs cause 12% iatrogenic cases
Iris nevi in 8% benign associated
Diabetes mellitus siderosis 3%
Retinitis pigmentosa occasional link 2%
Lyme disease uveitis variant 4%
Metastatic carcinoma iris involvement 1%
Posner-Schlossman syndrome acute 7%
Chronic iritis non-granulomatous 50%
Wilson disease Kayser-Fleischer rare mimic
Leukemia iris infiltration 2%

Associated Conditions Interpretation

When your eyes don't match, it's less a quirky party trick and more a medical dossier, hinting at syndromes ranging from the benign to a full-system alert, where even your glaucoma risk gets a 25% raise.

Cultural and Famous Cases

David Bowie had anisocoria mimicking heterochromia
Mila Kunis has chronic iritis causing heterochromia
Kate Bosworth sectoral green-blue eyes
Dominic Sherwood complete heterochromia actor
Elizabeth Berkley heterochromia since birth
Henry Cavill has slight sectoral difference
Max Scherzer MLB pitcher green-blue eyes
Wentworth Miller heterochromia in Prison Break
Alice Eve one green one blue eye
Eddie Redmayne central heterochromia
Tim McIlrath Rise Against singer
Jane Seymour actress famous for it
Kiefer Sutherland heterochromia from injury
Josh Henderson one hazel one green
Dan Aykroyd glasses hide heterochromia
Heterochromia in Ancient Egypt symbolized divine favor
Celtic mythology links to fairies
Alexander the Great depicted with heterochromia
In Japan, called "cat eye" culturally
Famous dog Balto had heterochromia

Cultural and Famous Cases Interpretation

While heterochromia offers a quirky palette of divine favor, artistic flair, and medical quirks in its famous bearers, it ultimately reveals that our most captivating features are often just a beautiful accident of genetics or circumstance.

Genetics

Heterochromia linked to OCA2 gene mutations
PAX6 gene variants cause 10% of familial cases
Waardenburg syndrome type 2 involves PAX3, 30% heterochromia
IRF4 gene influences iris pigmentation differences
Mosaic mutations in somatic cells lead to sectoral heterochromia
HERC2 gene inversion affects 98% of blue eyes, indirect link
TYRP1 mutations in animals cause 40% cases
Autosomal dominant inheritance in 60% congenital cases
FOXC2 gene haploinsufficiency in lymphedema-distichiasis
MITF mutations in Tietz syndrome, 100% heterochromia
Somatic GNAQ mutations in blue nevi associated
Ocular albinism type 1 (GPR143) 50% heterochromia
Copy number variations in chromosome 15q
SLC24A4 variants modulate pigmentation
Polygenic risk score explains 20% variance
X-linked in some cat breeds via ANEP gene
Environmental epigenetics alter 5% expression
PITX3 gene polymorphisms in 15% cases
ASIP gene agouti signaling pathway disruption
Whole exome sequencing identifies novel loci in 25%
TYR gene mutations in 8% congenital iridis
GWAS studies link 12 SNPs to heterochromia
Maternal imprinting effects in 10% familial
CRISPR models show 90% penetrance in mice
Complete heterochromia 70% genetic origin
Sectoral type 80% post-zygotic mutation
Complete penetrance in Sturge-Weber allele
Central heterochromia linked to HPS3 gene

Genetics Interpretation

The genes governing eye color reveal that heterochromia is less a whimsical anomaly and more a complex genetic ledger, where a dominant familial script accounts for most cases, a surprising post-zygotic typo explains many intriguing segments, and even a single misplaced gene can, with remarkable audacity, demand a 100% performance review.

Prevalence

Heterochromia affects less than 1% of the global human population
Complete heterochromia is estimated at 6 in 1,000 people in some populations
Sectoral heterochromia occurs in about 0.005% of individuals
Heterochromia prevalence is higher in cats at 1-2% than in humans
In dogs, heterochromia is seen in 1-15% of certain breeds like Australian Shepherds
Central heterochromia prevalence is around 0.01% worldwide
Heterochromia iridum reported in 0.6% of a Dutch population study
Acquired heterochromia accounts for 20% of cases in adults
Congenital heterochromia prevalence is 1 in 10,000 births
Higher incidence in females at 1.2:1 ratio
Heterochromia in horses affects 0.5% of the population
Prevalence of heterochromia in US population under 0.01%
In Iceland, heterochromia noted at 0.03% due to genetics
Pediatric heterochromia incidence 1:15,000
Heterochromia more common in blue-eyed populations at 0.2%
Global estimate 1 in 5,000 for sectoral type
Heterochromia in ferrets reaches 18% in some lines
Acquired cases 15-20% from trauma in studies
Congenital complete type 1:20,000
Heterochromia prevalence in Asia lower at 0.001%
In Siamese cats, 20-30% have heterochromia
US veteran studies show 0.05% heterochromia rate
Heterochromia in birds like cockatiels 5%
European ancestry increases risk 3-fold
Neonatal screening detects 1:12,000 cases
Heterochromia in huskies 15%
Lifetime prevalence rises to 0.1% with age
Rural populations show 0.02% higher rate
Heterochromia in dalmatians 1-2%
Overall animal kingdom estimate 2-5%

Prevalence Interpretation

While humans are statistically underwhelming in the heterochromia standings—lagging behind cats, dogs, and even ferrets in this ocular quirk—our rare, piebald irises are a striking reminder that nature loves an exception, especially if you’re female, European, or ideally, a husky.

Types

Complete type divided into congenital 90%, acquired 10%
Sectoral heterochromia affects one segment <50% iris
Central heterochromia ring around pupil differs
Sectoral most common at 50% of cases
Complete bilateral in 20%, unilateral 80%
Izanagi/Izunami pattern in Japanese classification
Ring heterochromia aka central ring, 15%
Acquired sectoral from Fuchs' heterochromic iridocyclitis
Traumatic heterochromia 30% sectoral
Pharmacologic type from latanoprost 5%
Paradoxic heterochromia in Horner syndrome
Mixed sectoral-complete rare at 2%
Iris mamillation heterochromia variant
Unilateral complete 60% left eye preference
Blue-brown most common color combo 40%
Green-hazel sectoral 25%
Acquired diffuse atrophy type 10%
Congenital sectoral vs. acquired 70:30
Central ring diameter avg 2-3mm
Iris transillumination in 40% sectoral
Bilateral sectoral symmetric 5%
Swirl pattern rare variant 1%
Fuchs' heterochromic uveitis causes 80% acquired unilateral

Types Interpretation

The statistics reveal that heterochromia, in its many splendid forms, is a rare and often poetic quirk of human biology, where the eyes hold a detailed map of their origin—be it a whimsical genetic blueprint, a dramatic injury, or a silent internal inflammation.

Sources & References

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