title: Co-occurrence of mosaic supernumerary isochromosome 18p and intermittent 2q13 deletions in a child with multiple congenital anomalies.
abstract: The present study deals with karyotpye-phenotype correlations in a six month old child with multiple congenital abnormalities. Cytogenetic analysis revealed mosaicism of a small metacentric supernumerary marker chromosome with a karyotype mos 47,XY+mar[34]/46,XY[31]. Cytogenetic microarray result showed three copies of chromosome 18p (15,400 kb in size). Moreover, 255 kbp intermittent deletion of chromosome 2q13 involving RGPD5, RGPD6, LIMS3, and LIMS3-LOC440895 was also observed. Correlating microarray data with the mosaic karyotype, the marker chromosome was identified as mosaic isochromosome 18p and was found to be 32,600 kbp in size. Baby resembled clinical characteristics of trisomy chromosome 18p, isochromosome 18p and trisomy chromosome 18. The present study suggested that deletion of evolutionarily conserved developmental genes (RGPD5, RGPD and LIMS3) in the 2q13 region might have contributed to more severity in phenotype as compared to so far such reported cases of 18p trisomy's, as these are involved in nuclear-cytoplasm trafficking, signaling for tissue patterning and differentiation.
authors.affiliation: Centre for Genetic Disorders, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India. Electronic address: sushil.biotech@yahoo.co.in.
authors.forename: Sushil Kumar
authors.initials: SK
authors.lastname: Jaiswal
authors.affiliation: Department of Pediatrics, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India. Electronic address: ashokkumar_bhu@hotmail.com.
authors.forename: Ashok
authors.initials: A
authors.lastname: Kumar
authors.affiliation: Centre for Genetic Disorders, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India. Electronic address: akhtar@bhu.ac.in.
authors.forename: Akhtar
authors.initials: A
authors.lastname: Ali
authors.affiliation: Centre for Genetic Disorders, Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India. Electronic address: akrai10@gmail.com.
authors.forename: Amit Kumar
authors.initials: AK
authors.lastname: Rai
mesh_terms: D000015:Abnormalities, Multiple / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D021581:Active Transport, Cell Nucleus; D002467:Cell Nucleus / Q000235:genetics* / Q000378:metabolism; D002872:Chromosome Deletion; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics* / Q000378:metabolism; D002889:Chromosomes, Human, Pair 2 / Q000235:genetics*; D006801:Humans; D007223:Infant; D008297:Male; D014314:Trisomy / Q000235:genetics / Q000473:pathology
keywords: Cytogenetic microarray; Marker chromosome; Mosaicism