Leber hereditary optic neuropathy in Australia

Area of Science:

• Ophthalmology
• Genetics
• Neurology

Background:

• Leber hereditary optic neuropathy (LHON) is a maternally inherited mitochondrial disease.
• It is characterized by acute or subacute central vision loss, predominantly affecting young males.
• LHON accounts for a significant percentage of irreversible blindness in Australia.

Purpose of the Study:

• To investigate the prevalence and characteristics of Leber hereditary optic neuropathy (LHON) in Australia.
• To identify families affected by LHON and assess the current status of affected individuals.
• To estimate the future burden of LHON-related vision loss in the Australian population.

Main Methods:

• Identification of 20 unrelated Australian families with mitochondrial DNA mutations linked to LHON.
• Analysis of 291 individuals with documented LHON diagnoses.
• Epidemiological assessment of disease onset, sex-specific risk, and carrier status.

Main Results:

• The mean age of vision loss onset in males was 26 years and in females was 27 years.
• The risk of vision loss was 20% for males and 4% for females.
• Over 1750 carriers are living in Australia, with 600 under 24 years old; 135 of 291 individuals are alive.
• An estimated 3-4 new cases of blindness annually are expected from LHON.

Conclusions:

• LHON represents a notable cause of vision impairment in Australia, particularly among young males.
• A substantial number of carriers are at risk of developing vision loss, highlighting the need for awareness and potential interventions.
• Ongoing monitoring and genetic counseling are crucial for families affected by LHON.