Sonic Hedgehog deletion and distal trisomy 3p in a patient with microphthalmia and microcephaly, lacking cerebral anomalies typical of holoprosencephaly.

Abstract

About 20% of cases with 7q deletion syndrome is associated with holoprosencephaly (HPE), due to deletion of the Sonic Hedgehog (SHH) gene (mapping to 7q36). The occurrence of severe forms of holoprosencephaly is higher in cases of 7q deletion associated with partial trisomies involving different parts of the genomes than in patients with pure 7q deletion. All cases of 7q deletion associated with 3p duplication reported to date have been associated with severe forms of holoprosencephaly, and a gene(s) on distal 3p has (have) been hypothesized to be responsible for HPE phenotype when in triple dose. Here we describe a patient with unbalanced 3p;7q translocation, showing 7q deletion (including SHH gene) and 3p duplication (complete karyotype was 46,XY,der(7)t(3;7)(p26.3;q36.1)), presenting with a relatively mild phenotype, consisting of microphthalmia and microcephaly, without cerebral anomalies typical of holoprosencephaly. Possible involvement of some genes on 3p in determining such a mild phenotype is discussed.

• Authors: Virginia M Ginocchio, Daniele De Brasi, Rita Genesio, Roberto Ciccone, Stefania Gimelli, Francesco Fimiani, Teresa de Berardinis, Lucio Nitsch, Sandro Banfi, Adriano Magli, Roberto Della Casa
• Journal: European journal of medical genetics (Eur J Med Genet) Vol. 51 Issue 6 Pg. 658-65 ( 2008) ISSN: 1878-0849 [Electronic] Netherlands
• PMID: 18762283 (Publication Type: Case Reports, Journal Article)

Chemical References

• Hedgehog Proteins
• SHH protein, human

Topics

• Abnormalities, Multiple (genetics)
• Chromosomes, Human, Pair 3
• Eye Abnormalities (genetics)
• Gene Deletion
• Hedgehog Proteins (genetics)
• Holoprosencephaly (genetics)
• Humans
• Infant, Newborn
• Karyotyping
• Male
• Microcephaly (genetics)
• Trisomy