Trisomy 1q32 and monosomy 11q25 associated with congenital heart defect: cytogenomic delineation and patient fourteen years follow-up

Silver-Russell syndrome-like features in a child with recombinant chromosome 11 derived from maternal pericentric inversion

Silver-Russell syndrome (SRS) is a well-known syndrome but with heterogeneous etiologies. We present the case of a child with severe SRS-like features resulting from a complex rearrangement of chromosome 11 inherited from his mother. We studied the index case with karyotyping, MS-MLPA and molecular karyotyping. The mother was studied with karyotyping and subtelomeric FISH. We found a child with marked developmental delay and fatal outcome due to failure to thrive, carrying an 11p15 duplication and an 11q25 deletion of maternal origin. We discovered that the mother was a carrier of a pericentric inversion of chromosome 11, with a history of recurrence in other family members who had severe growth retardation and early death. To our knowledge, no similar SRS-like cases have been described in the literature. This report supports the importance of identification the causative genetic mechanism in SRS-like individuals with duplication in 11p15 region due to high risk of recurrence and to provide an appropriate genetic counseling to the family.

Duplication of 1q31.3q41 in two affected siblings due to paternal insertional translocation

We report two sisters with developmental delay and dysmorphic features, as well as a history of seizures. Both sisters have short stature, microcephaly and shared facial dysmorphisms. We detected an 18.1 Mb interstitial gain in 1q31.3q41 and a 140 kb interstitial loss in 7p11.2 in both siblings by using array analysis in the older sister and copy number variation analysis in whole exome sequencing data in the younger sister. We further examined parental chromosomes and found an insertional translocation in the unaffected father, having a 46,XY,ins(7;1)(p11.2;q31.3q41) karyotype. A 1.8 Mb loss at the rearranged 1q segment was subsequently detected on additional array analysis in the father, as well as the 140 kb loss in 7p11.2. We describe the clinical consequences of the 18.1 Mb duplication of the long arm of chromosome 1 due to an unbalanced paternal insertional translocation and compare these with the clinical phenotypes of patients with an overlapping 1q duplication.