Br J Ophthalmol 1998;82:1280-1284 ( November )
Severe form of juvenile corneal stromal dystrophy with homozygous
R124H mutation in the keratoepithelin gene in five Japanese patients
Yukihiko Mashima,a
Minako Konishi,a
Yu Nakamura,a
Yutaka Imamura,a
Masakazu Yamada,a
Tetsuya Ogata,a
Jun Kudoh,b
Nobuyoshi Shimizub
a Departments of Ophthalmology, Keio University School of
Medicine, Tokyo, Japan, b Molecular Biology, Keio University School of Medicine, Tokyo,
Japan
Correspondence to: Yukihiko Mashima, MD,
Department of Ophthalmology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo 160, Japan.
Accepted for publication 7 May 1998
AIM
To confirm the mutation of the keratoepithelin
gene in patients with a severe form of superficial juvenile granular
corneal dystrophy (GCD).
METHODSFive Japanese probands in whom GCD was
diagnosed after histopathological examination and who developed
severe manifestations of GCD in their first decade of life were
investigated. Other affected family members of two probands were also
examined. All probands were the offspring of consanguineous parents.
DNA was extracted from their peripheral blood leucocytes and mutational analysis of the gene was performed by the polymerase chain reaction and
direct sequencing.
RESULTSFour of the five probands underwent their
first keratectomy or keratoplasty in their teens and subsequently
underwent a second or third keratoplasty. Each proband had a homozygous
G 
A transition at codon 124, replacing Arg His, of the
keratoepithelin gene. Their moderately affected family members were
heterozygous for the mutation.
CONCLUSIONSThis finding suggests that the
severity of the corneal phenotype depends on the dose effect of the
mutant gene.
Keywords:
Avellino corneal dystrophy;
keratoepithelin;
R124H
mutation;
homozygote
© 1998 by British Journal of Ophthalmology
