Eggermann et al have suggested that the apparent upd(6)mat “phenotype" is a result of placental
trisomy 6 mosaicism (Eggermann T et al,
Maternal UPD was detected in a developmentally normal patient (van den Berg-Loonen EM et al 1996) and has
been associated with IUGR (Spiro RP et al 1999; Lazier J et al 2016).
Cockwell AE et al (2006) described a
mosaic trisomy 6 with mosaic maternal heterodisomy, that had an atrial septal defect, exomphalos and
death at 23 weeks gestation.
Salahshourifar I et al (2010) reported
cleft lip and palate in a boy with maternal heterodisomy of chromosome 6.
A Japanese patient had 3M syndrome (characterised by severe pre- and post-natal growth retardation)
maternal UPD that revealed mutations in the CUL7 gene (Sasaki K et al 2011).
In a cohort of patients with cone disorders (cone dystrophy (CD) and cone-rod dystrophy (CRD))
mapping and segregation analysis revealed maternal UPD in a patient. In this case, maternal UPD
mutation in the TULP1 gene (Roosing S et al
Paternal UPD is discussed in the 6q entry on transient neonatal diabetes mellitus (TNDM).