Inv dup del(9p): Prenatal diagnosis and molecular cytogenetic characterization by fluorescence in situ hybridization and array comparative genomic hybridization

Abstract

Fluorescence in situ hybridization and array comparative genomic hybridization are useful to determine the nature of a prenatally detected aberrant chromosome derived from the inv dup del. Male fetuses with inv dup del(9p) and haploinsufficiency of DMRT1 and DMRT3 may present normal male external genitalia without sex reversal.

Another Rare Case of a Child with de novo Terminal 9p Deletion and Co-Existing Interstitial 9p Duplication: Clinical Findings and Molecular Cytogenetic Study by Array-CGH

“…Another patient with similar breakpoint was reported by Chen et al [2011]; the features of the terminated fetus are similar to our patient, but it is always difficult to predict postnatal phenotype based on prenatal data.…”

“…No precise breakpoints available. mined by use of high resolution array: the patients reported by Hulick et al [2009]: Agilent 244K array, Chen et al [2011]: Agilent 60K array and our case: Agilent 244K. In 2 cases the breakpoints were characterized by use of BAC arrays [Faas et al, 2007;Swinkels et al, 2008] and in all other cases the breakpoints are estimated based on cytogenetic and FISH results.…”

“…For example, the size of the terminal deletion of 9p significantly influences the phenotype. The male fetus with a very small 9p deletion (0.7 Mb) and with deleted DMRT1 gene, the strongest candidate gene in XY gonadal dysgenesis [Ledig et al, 2010], still has normal male genitalia [Chen et al, 2011], whereas the genetically male patient reported by Muroya et al [2000] with 3 Mb deletion has female external genitalia. In the cases of Faas et al [2007] and Swinkels et al [2008] the 9p deletion is the largest, and they reveal more severe phenotypes when compared to our case.…”

“…References marked with an asterisk: breakpoints of the rearrangement were assessed based on the marker/FISH analysis or converted from another genome build (breakpoints assessed between the known markers or in the middle of chromosome band to visualize the abnormality in UCSC browser). There are only 3 cases, where breakpoints were tested with high resolution array: our case (Agilent 244K), Hulick et al [2010] (Agilent 244K array) and Chen et al [2011] (Agilent 60K array). Two studies revealed breakpoints by using BAC arrays [Faas et al, 2007;Swinkels et al, 2008].…”

Case Report Familial balanced translocation leading to an offspring with phenotypic manifestations of 9p syndrome

“…Thus, it can be stated that the deletion in the region of the short arm of chromosome 9p has a minimum length of ~1 Mb, where the genes DOCK8, KANK1, and DMRT1 are located. Specifically, deletion of the DOCK8 gene has been associated with mental retardation (Chen et al, 2011). Griggs et al (2008) also described two unrelated patients (one male and one female) with mental deficiency and developmental disability, who had a heterozygous disruption of the DOCK8 gene, in which the male had a genomic deletion of approximately 230 kb in subtelomeric 9p, while the female carried a de novo balanced translocation t(X;9)(q13.1;p24).…”