A New Zealand and a Scottish pedigree with maternally inherited sensorineural deafness were both previously shown to carry a heteroplasmic A7445G mutation in the mitochondrial genome. More detailed clinical examination of the New Zealand family showed that the hearing loss was progressive, with the
A novel mitochondrial point mutation in a maternal pedigree with sensorineural deafness
โ Scribed by Fiona M. Reid; Guy A. Vernham; Howard T. Jacobs
- Publisher
- John Wiley and Sons
- Year
- 1994
- Tongue
- English
- Weight
- 647 KB
- Volume
- 3
- Category
- Article
- ISSN
- 1059-7794
No coin nor oath required. For personal study only.
โฆ Synopsis
We have detected a novel mitochondrial mutation in a maternal pedigree, at least 13 of whose members have sensorineural hearing loss of varying severity, but who exhibit no other pathological features. The mutation, at np 7445, converts the 3' terminal T residue of tRNA-ser(UCN) to a C, and also brings about a silent alteration to the COI stop codon. The mutation destroys an XbaI site, within which a second mutation, at np 7444, has previously been reported in association with Leber's hereditary optic neuropathy. Predominantly mutant mtDNA was found in all 13 family members surveyed, whether or not they are overtly affected by deafness, and some individuals appeared homoplasmic, within the limits of detection. The novel mutation was not found in over 600 normal controls, nor in any of 27 other maternally unrelated individuals with deafness Other mutations found in mitochondrial disorders were also absent from this pedigree.
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