Complex sentence: The Syndrome is usually caused by an mUPD on chromosome 7, in 7% of the cases, which is an imprinting error where the person receives two copies of chromosome 7 from the mother (maternally inherited).
Split into simpler sentences: The Syndrome is usually caused by an mUPD on chromosome 7, in 7% of the cases. Which is an imprinting error where the person receives two copies of chromosome 7 from the mother (maternally inherited).