• Objective.
—To study the inheritance of the X-linked lymphoproliferative disease (XLP) locus in a German family.
Design.
—Haplotype segregation analysis.
Setting.
—Departments of Pediatrics and Human Genetics, University of Würzburg and University of Ulm, Federal Republic of Germany.
Participants.
—Fourteen members of a family with XLP.
Interventions.
—None.
Measurements/Main Results.
—Using molecular genetic techniques, we diagnosed the XLP status of the members of a German family. Restriction fragment length polymorphism analysis with closely linked polymorphic X-chromosomal DNA markers (Xq25-q27) revealed XLP carrier status in a female infant. Moreover, the XLP mutation was suggested to have occurred in the germ cell of the grandfather.
Conclusion.
—This is the first report of a paternally inherited XLP mutation. The recurrence risk for germ cell mosaicism in XLP may be similar to that of X-linked Duchenne muscular dystrophy.(AJDC. 1993;147:1303-1305)