Carrier detection in Wiskott-Aldrich syndrome: combined use of M27 beta for
X-inactivation studies and as a linked probe
J Goodship, J Carter, T Espanol, Y Boyd, S Malcolm and RJ Levinsky
Department of Human Genetics, Newcastle upon Tyne, UK.
Wiskott-Aldrich syndrome (WAS) is an X-linked immunodeficiency disorder
with no clinical or immunologic abnormalities in carrier females. The
defective gene has been localized to proximal Xp. Carrier females have
nonrandom use of the X chromosome in granulocytes, lymphocytes, and
monocytes. We have used the probe M27 beta, which detects both a variable
number tandem repeat polymorphism and methylation differences between the
active and inactive X chromosome, in the investigation of families referred
for genetic counseling. M27 beta detects the locus DXS255, which is tightly
linked to WAS. As the probe that is used for investigation of
X-inactivation patterns is also linked to the disease locus, it is possible
to assign phase in families where this could not be done by conventional
use of linked probes. The mothers of four isolated male cases had nonrandom
use of the X chromosome. A new mutation was identified in one family with
two affected males.
Volume 77,
Issue 12,
pp. 2677-2681,
06/15/1991
Copyright © 1991 by The American Society of Hematology
