Identification of an E689K substitution as the molecular basis of the human acid alpha-glucosidase type 4 allozyme (GAA*4).
We have identified the molecular basis of the GAA*4 allozyme as a G to A transition at nt2065 which predicts the substitution of glutamic acid by lysine at codon 689 (E689K). The conclusion that this change represents the molecular basis of the GAA*4 allozyme is based on 1) presence of the G2065A in homozygosity in a known GAA*4 homozygote, 2) transient expression studies showing normal enzyme activity expressed by cDNA containing the G2065A transition and 3) isoelectric focusing studies showing a more cathodal pattern for the expressed product as compared to the common GAA*1, analogous to the patterns seen in normal and known GAA*4 lymphoid cells.
New York University Medical Center, Department of Medicine, New York, New York 10016, USA.
M L
ML
Huie
M
M
Menaker
P J
PJ
McAlpine
R
R
Hirschhorn
D044466:Asian People; D002460:Cell Line; D005091:Exons; D018698:Glutamic Acid / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D007564:Japan / Q000208:ethnology; D008221:Lymphoid Tissue / Q000166:cytology; D009154:Mutation; D017422:Sequence Analysis, DNA
D018698:Glutamic Acid