Clinical Potential of Effective Noninvasive Exclusion of KEL1-Positive Fetuses in KEL1-Negative Pregnant Women.
BACKGROUND
The clinical importance of assessing the fetal KEL genotype is to exclude 'K'-positive fetuses (genotype KEL1/KEL2) in 'K'-alloimmunized pregnant women (genotype KEL2/KEL2). Noninvasive assessment of the fetal KEL genotype is not yet available in the Czech Republic.


OBJECTIVE
The aim of this study was to assess the fetal KEL1/KEL2 genotype from cell-free fetal DNA in the plasma of KEL2/KEL2 pregnant women.


METHODS
The fetal genotype was assessed by minisequencing (a dilution series including control samples). A total of 138 pregnant women (between the 8th and 23rd gestational week) were tested by minisequencing. The fetal genotype was further verified by analysis of a buccal swab from the newborn.


RESULTS
Minisequencing proved to be a reliable method. In 2.2% (3/138) of the examined women, plasma sample testing failed; 94.8% (128/135) had the KEL2/KEL2 genotype, and a total of 3.1% of fetuses (4/128) had the KEL1/KEL2 genotype. Sensitivity and specificity reached 100% (p < 0.0001).


CONCLUSIONS
Minisequencing is a reliable method for the assessment of the fetal KEL1 allele from the plasma of KEL2/KEL2 pregnant women.
University Hospital and Palacky University Olomouc, Olomouc, Czech Republic.
Jana
J
Böhmova
Radek
R
Vodicka
Marek
M
Lubusky
Iva
I
Holuskova
Martina
M
Studnickova
Romana
R
Kratochvilova
Eva
E
Krejcirikova
Maria
M
Janikova
Veronika
V
Durdová
Tereza
T
Dolezalová
Hana
H
Filipová
Ladislav
L
Dusek
Ishraq
I
Dhaifalah
Katherine
K
Vomackova
Marian
M
Kacerovsky
Martin
M
Prochazka
Radek
R
Vrtel
D000328:Adult; D001789:Blood Group Antigens / Q000235:genetics*; D004899:Erythroblastosis, Fetal / Q000175:diagnosis; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D005333:Fetus; D060005:Genotyping Techniques; D006801:Humans; D008562:Membrane Glycoproteins / Q000235:genetics*; D008666:Metalloendopeptidases / Q000235:genetics*; D011247:Pregnancy; D012680:Sensitivity and Specificity
D001789:Blood Group Antigens; D008562:Membrane Glycoproteins; C585978:KEL protein, human; D008666:Metalloendopeptidases