Abstract: The invention concerns a method for the determination of data for the preparation of presymptomatic or prenatal diagnosis of phakomatosis, in particular, a tumor suppressor gene disease, in a high-risk patient, in particular of neurofibromatosis, comprising the steps of: making available the tumor material from a person afflicted with the tumor suppressor gene disease, who is a relative of the high-risk patient; isolating tumor DNA from the tumor in the relative; isolating blood DNA from the blood of the relative; amplifying polymorphous DNA microsatellite markers from the tumor and the blood; separating the markers by length; observing the lengths of the markers; comparing the markers from the blood and the tumor; examining for a loss of alleles; optionally, comparing amplified markers from a second tumor of the relative; and amplifying polymorphous DNA microsatellite markers from the blood of an offspring and separating and observing the markers.

Abstract: The invention concerns a method for the determination of data for the preparation of presymptomatic or prenatal diagnosis of phakomatosis, in particular, a tumor suppressor gene disease, in a high-risk patient, in particular of neurofibromatosis, comprising the steps of: making available the tumor material from a person afflicted with the tumor suppressor gene disease, who is a relative of the high-risk patient; isolating tumor DNA from the tumor in the relative; isolating blood DNA from the blood of the relative; amplifying polymorphous DNA microsatellite markers from the tumor and the blood; separating the markers by length; observing the lengths of the markers; comparing the markers from the blood and the tumor; examining for a loss of alleles; optionally, comparing amplified markers from a second tumor of the relative; and amplifying polymorphous DNA microsatellite markers from the blood of an offspring and separating and observing the markers.

Abstract: The invention concerns a method for the determination of data for the preparation of presymptomatic or prenatal diagnosis of phakomatosis, in particular, a tumor suppressor gene disease, in a high-risk patient, in particular of neurofibromatosis, comprising the steps of: making available the tumor material from a person afflicted with the tumor suppressor gene disease, who is a relative of the high-risk patient; isolating tumor DNA from the tumor in the relative; isolating blood DNA from the blood of the relative; amplifying polymorphous DNA microsatellite markers from the tumor and the blood; separating the markers by length; observing the lengths of the markers; comparing the markers from the blood and the tumor; examining for a loss of alleles; optionally, comparing amplified markers from a second tumor of the relative; and amplifying polymorphous DNA microsatellite markers from the blood of an offspring and separating and observing the markers.

Abstract: The invention concerns a method for the determination of data for the preparation of presymptomatic or prenatal diagnosis of phakomatosis, in particular, a tumor suppressor gene disease, in a high-risk patient, in particular of neurofibromatosis, comprising the steps of: making available the tumor material from a person afflicted with the tumor suppressor gene disease, who is a relative of the high-risk patient; isolating tumor DNA from the tumor in the relative; isolating blood DNA from the blood of the relative; amplifying polymorphous DNA microsatellite markers from the tumor and the blood; separating the markers by length; observing the lengths of the markers; comparing the markers from the blood and the tumor; examining for a loss of alleles; optionally, comparing amplified markers from a second tumor of the relative; and amplifying polymorphous DNA microsatellite markers from the blood of an offspring and separating and observing the markers.