To investigate whether Y chromosomal genetic material has a role in the development of Müllerian aplasia in Finland. We have studied the TSPY1 gene and 38 additional male-specific fragments covering areas of both the long and short arms of the Y chromosome in Finnish patients with Müllerian aplasia.A retrospective study.University hospital and genetic laboratory.A sample set of 110 Finnish patients with well-diagnosed Müllerian aplasia and 20 healthy relatives (13 mothers, 4 fathers, and 3 sisters from different families) were included in the study. One hundred healthy female controls with a background of at least one normal pregnancy with delivery were used as controls.Blood samples for DNA extraction.Detection of Y chromosomal fragments by polymerase chain reaction in female patients with Müllerian aplasia.None of the female patients showed presence of the earlier reported TSPY1 gene or 38 additional Y chromosomal markers.Our results indicate that the studied Y-specific fragments, namely TSPY1 and 38 Y chromosomal markers, are not responsible for the syndrome in these Finnish patients with Müllerian aplasia.