A large GLC1C Greek family with a myocilin T377M mutation: inheritance and phenotypic variability.
OBJECTIVE
POAG is a complex disease; therefore, families in which a glaucoma gene has been mapped may carry additional POAG genes. The goal of this study was to determine whether mutations in the myocilin (MYOC) gene on chromosome 1 are present in two POAG families, which have previously been mapped to the GLC1C locus on chromosome 3.


METHODS
The three exons of MYOC were screened by denaturing (d)HPLC. Samples with heteroduplex peaks were sequenced. Clinical findings were compared with genotype status in all available family members over the age of 20 years.


RESULTS
A T377M coding sequence change in MYOC was identified in family members of the Greek GLC1C family but not in the Oregon GLC1C family. Individuals carrying both the MYOC T377M variant and the GLC1C haplotype were more severely affected at an earlier age than individuals with just one of the POAG genes, suggesting that these two genes interact or that both contribute to the POAG phenotype in a cumulative way.
Petersen
Michael B
MB
Department of Genetics, Institute of Child Health, Athens, Greece.
Kitsos
George
G
Samples
John R
JR
Gaudette
N Donna
ND
Economou-Petersen
Effrosini
E
Sykes
Renée
R
Rust
Kristal
K
Grigoriadou
Maria
M
Aperis
George
G
Choi
Dongseok
D
Psilas
Konstantinos
K
Craig
Jamie E
JE
Kramer
Patricia L
PL
Mackey
David A
DA
Wirtz
Mary K
MK
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002851:Chromatography, High Pressure Liquid; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics*; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics*; D003598:Cytoskeletal Proteins / Q000235:genetics*; D004252:DNA Mutational Analysis; D005091:Exons / Q000235:genetics; D005136:Eye Proteins / Q000235:genetics*; D005260:Female; D005838:Genotype; D005902:Glaucoma, Open-Angle / Q000208:ethnology / Q000235:genetics*; D006023:Glycoproteins / Q000235:genetics*; D006115:Greece / Q000208:ethnology; D006239:Haplotypes; D020180:Heteroduplex Analysis; D006801:Humans; D040582:Inheritance Patterns; D008297:Male; D008875:Middle Aged; D009154:Mutation; D010375:Pedigree; D010641:Phenotype; D016133:Polymerase Chain Reaction; D000099179:Myocilin
D003598:Cytoskeletal Proteins; D005136:Eye Proteins; D006023:Glycoproteins; D000099179:Myocilin