Maternal uniparental disomy 7--review and further delineation of the phenotype

Eur J Pediatr. 2000 Apr;159(4):247-56. doi: 10.1007/s004310050064.


Uniparental disomy (UPD) is defined as the inheritance of both homologous chromosomes from only one parent. So far, maternal UPD 7 has been described in 28 cases. Here, we report 4 new cases, present clinical information of 5 cases previously reported by us, and review the clinical and molecular findings of all 32 cases. We found a phenotype characterized by pre- and postnatal growth retardation, occipitofrontal head circumference in the lower normal range, a triangular face, and retarded bone maturation. Findings of the facial gestalt included a high and broad forehead and a pointed chin. A broad mouth with down-turned corners, prominent ears, café-au-lait spots, hemihypotrophy, or clinodactyly were rarely present. Psychomotor development was delayed in 6 cases. The clinical findings strikingly resemble the phenotype of the heterogeneous Silver-Russell syndrome (SRS). Other anomalies were less frequently found than in SRS. Molecular investigations revealed 11 cases with isodisomy and 17 cases with heterodisomy. In 4 cases this information was not available. From the allelic distribution of the microsatellites investigated, 9 cases might be the consequence of an error at maternal meiosis I, and 6 cases might be due to non-disjunction at maternal meiosis II. Three of the 17 heterodisomic cases had trisomy 7 in chorionic villi, in the remaining cases no prenatal diagnosis through chorionic villus sampling was reported.

Conclusion: Maternal UPD 7 should investigated in children with pre- and postnatal growth retardation anda facial gestalt characterized by a high and broad forehead and a pointed chin, as well as in cofined placental mosaicism for trisomy 7.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Abnormalities, Multiple / genetics*
  • Child
  • Chromosome Aberrations*
  • Chromosomes, Human, Pair 7 / genetics*
  • Developmental Disabilities / genetics
  • Facies
  • Female
  • Fetal Growth Retardation / genetics
  • Humans
  • Male
  • Microsatellite Repeats / genetics
  • Phenotype
  • Psychomotor Performance
  • Syndrome