New case of "apple-peel" intestinal atresia and ocular anomalies with mosaic variegated aneuploidy

Expanding the phenotype and the genotype of Stromme syndrome: A novel variant of the CENPF gene and literature review

This report describes siblings with Stromme syndrome, a rare genetic condition that primarily presents with a triad of intestinal atresia, cranial and ocular malformations, and other organ systems could be involved. This clinical triad was initially named after the first person to describe it in 1993. Here, we report a family with two siblings who presented with unusual intestinal atresia and ocular and CNS abnormalities. The first patient is a 6-year-old-boy with apple peel duodeno-jejunal atresia, unilateral microphthalmia and microcephaly. The second patient, a younger brother, presented with intestinal atresia, corneal opacity and alobar holoprosencephaly and passed away at the age of 3 months. Exome sequencing showed a novel homozygous variant in the CENPF gene, NM_016343.3: c.1195-2 A > G that was detected in both of the affected siblings. This is a report and literature review of CENPF-related ciliopathy, which may result in Stromme syndrome. As this is the fourth report linking the CENPF gene variant with Stromme syndrome and first reported case presented with holoprosencephaly, it will expand the current knowledge on the genotype and the phenotype of Stromme syndrome.

Strømme Syndrome Is a Ciliary Disorder Caused by Mutations in CENPF

Strømme syndrome was first described by Strømme et al. (1993) in siblings presenting with "apple peel" type intestinal atresia, ocular anomalies and microcephaly. The etiology remains unknown to date. We describe the long-term clinical follow-up data for the original pair of siblings as well as two previously unreported siblings with a severe phenotype overlapping that of the Strømme syndrome including fetal autopsy results. Using family-based whole-exome sequencing, we identified truncating mutations in the centrosome gene CENPF in the two nonconsanguineous Caucasian sibling pairs. Compound heterozygous inheritance was confirmed in both families. Recently, mutations in this gene were shown to cause a fetal lethal phenotype, the phenotype and functional data being compatible with a human ciliopathy [Waters et al., 2015]. We show for the first time that Strømme syndrome is an autosomal-recessive disease caused by mutations in CENPF that can result in a wide phenotypic spectrum.

Exclusion of a PAX6, FOXC1, PITX2, and MYCN mutation in another patient with apple peel intestinal atresia, ocular anomalies and microcephaly and review of the literature

We describe another patient with the combination of apple peel intestinal atresia, microcephaly, microphthalmia, and anterior eye chamber anomalies. Development so far seems to be normal, although there is major visual impairment due to the corneal clouding. Mutation analysis of the PAX6, FOX1, PITX2, and MYNC genes was normal as was MLPA for these genes. Autosomal recessive inheritance is possible as recurrence in sibs was described, although germ line mosaicism or a microdeletion due to a very small parental translocation cannot be ruled out.

Induction of premature chromatid separation (PCS) in individuals with PCS trait and in normal controls

Cultured peripheral blood lymphocytes from ten normal individuals, treated with 0.075 M KCl at 37 degrees C for 20 min, showed 0-2% cells in premature chromatid separation (PCS), a configuration with split centromeres and chromatids of most or all chromosomes. When treated for 30 min, they increased to 19% in the average, and at 45 min to 63%. Similar and significant effects of temperature and duration of hypotonic treatment on the frequencies of PCSs were found also in mitotic lymphocytes from patients with homozygous PCS trait, a cancer-prone disorder with >50% lymphocytes in PCS, mosaic variegated aneuploidy, and a variety of clinical manifestations; and from their heterozygous carrier parents. B lymphoblastoid cells from two infants with the homozygous PCS trait did not show PCSs when processed without hypotonic treatment. The frequencies of their PCSs increased with increasing temperature and duration of hypotonic treatment, attaining more than 65% after 20 min treatment and 90% after 45 min at 37 degrees C. PCS is thus likely to be induced largely by hypotonic treatment. Treatment at 37 degrees C for 20 min was found to be most suitable for the count of PCSs, in which the frequency of PCSs becomes almost zero in cells from normal individuals, and the difference in frequency of PCSs was most remarkable between the patients and heterozygous carriers, and between the heterozygous carriers and normal individuals. Chromosomes from the patients with the homozygous PCS trait tended to be long, and their PCSs tended to have a large number of widely separated sister chromatids. Chromosomes from normal individuals tended to be short, and the sister chromatids in their PCSs were set close to each other.