Related Experiment Videos
Does mitochondrial genome mutation in subjects with maternally inherited diabetes and deafness decrease severity of
D J Holmes-Walker1, P Mitchell, S C Boyages
1Department of Diabetes and Endocrinology, Westmead Hospital, NSW, Australia. janeh@westmed.wh.usyd.edu.au
Diabetic Medicine : a Journal of the British Diabetic Association
|November 25, 1998
Summary
Maternal inheritance diabetes and deafness (MIDD) subjects show reduced diabetic retinopathy, possibly due to lower polyol pathway glucose metabolism. Abnormal glucose tolerance is linked to pigmentary retinopathy in these individuals.
Area of Science:
- Ophthalmology
- Genetics
- Metabolic Disorders
Background:
- Maternal inheritance diabetes and deafness (MIDD) is associated with mitochondrial mutations.
- The interplay between MIDD, diabetic retinopathy, and pigmentary retinopathy is not well understood.
- Mitochondrial mutations may influence glucose metabolism and diabetic retinopathy development.
Purpose of the Study:
- To investigate the prevalence of diabetic and pigmentary retinopathy in MIDD kindreds.
- To explore the relationship between mitochondrial mutations, glucose metabolism, and retinopathy.
- To determine if diabetic retinopathy is altered in MIDD subjects.
Main Methods:
- Studied 61 family members from five MIDD kindreds, including 12 with diabetes and 11 without.
- Assessed retinopathy severity via slit lamp biomicroscopy, retinal photography, and fluorescein angiography.
- Measured red blood cell sorbitol and glucose levels in MIDD subjects and controls.
Main Results:
- Diabetic retinopathy was absent in 75% of diabetic MIDD subjects; none had cataracts.
- Red blood cell sorbitol levels were significantly lower in MIDD subjects compared to diabetic controls.
- Pigmentary retinopathy was present in 15/23 subjects, strongly associated with abnormal glucose tolerance (OR 19.5, p=0.008).
Conclusions:
- MIDD subjects exhibit a decreased prevalence of diabetic retinopathy and cataract, potentially due to reduced polyol pathway activity.
- Abnormal glucose tolerance exacerbates the clinical expression of pigmentary retinopathy in individuals with mitochondrial mutations.
- Understanding mitochondrial DNA mutation effects may reveal mechanisms underlying diabetic retinopathy and diabetes complications.