Tightly linked polymorphic markers for fragile X syndrome and prenatal cytogenetic diagnostic experience.
Linkage analysis using the polymorphic loci DXS369, DXS296, DXS297 and DXS306 was carried out on a cohort of 17 families segregating for fragile X syndrome. The observed recombination fractions at: DXS369 (Zmax = 3.02; theta = 0.06), DXS297 (Zmax = 2.92; theta = 0.0), DXS296 (Zmax = 3.82; theta = 0.0), DXA306 (Zmax = 4.55; theta = 0.05) confirm that these loci are tightly linked to FRAXA. Our experience in the cytogenetic analysis of 58 at risk pregnancies by chorionic villus or fetal blood sample examination documents a false negative rate in obligate carrier male pregnancies for CVS of 11% and for FBS of 3%.
Glass
I A
IA
Dept of Clinical Genetics, University of Birmingham.
Del Mastro
R G
RG
Lanyon
W G
WG
Raeburn
J A
JA
Kilpatrick
M W
MW
Webb
T P
TP
Connor
J M
JM
D003582:Cytogenetics; D004247:DNA / Q000235:genetics; D005260:Female; D005600:Fragile X Syndrome / Q000175:diagnosis / Q000235:genetics*; D006580:Genetic Carrier Screening; D008040:Genetic Linkage; D005819:Genetic Markers; D006801:Humans; D008297:Male; D011110:Polymorphism, Genetic; D011247:Pregnancy; D011296:Prenatal Diagnosis
D005819:Genetic Markers; D004247:DNA