RESUMEN
Individuals with pericentric inversions are at risk for producing offspring with chromosomal gains and losses, while those carrying paracentric inversions usually produce unviable gametes [Madan, 1995]. In this current study, we present a newborn with dysmorphic features and malformations, whose karyotype showed an abnormal copy of chromomosome 7 described at first as add(7)(q32) as well as mos 45,X/47,XXX. Array comparative genomic hybridization (CGH) revealed an interstitial deletion in the long arm of chromosome 7 involving bands q35 to q36.3 but retaining the 7q subtelomere. The patient's deletion is believed to be due to meiotic recombination in the inversion loop in the phenotypically normal father who seems to carry two paracentric inversions in the long arm of chromosome 7, which was described as rec(7)(7pter- > q35::q36.3- > 7qter)pat. The abnormal copy of chromosome 7 in the father has been described as: der(7)(7pter- > q22.1::q36.3- > q35::q22.1- > q35::q36.3- > 7qter). This is a unique karyotype that to our knowledge has not been previously reported in the literature and predisposes to meiotic recombination that can result in deletions or duplications of 7q35-36.
Asunto(s)
Cromosomas Humanos Par 7/genética , Mosaicismo , Recombinación Genética , Deleción Cromosómica , Inversión Cromosómica/genética , Cromosomas Humanos X/genética , Hibridación Genómica Comparativa , Femenino , Estudios de Seguimiento , Humanos , Hibridación Fluorescente in Situ , Recién Nacido , Cariotipo , Meiosis , Aberraciones Cromosómicas Sexuales , Trastornos de los Cromosomas Sexuales del Desarrollo Sexual/genética , Trisomía/genéticaRESUMEN
Partial trisomy 2p is typically associated with partial monosomy of another chromosomal segment and results from a balanced translocation in one of the parents. Inverted duplications with terminal deletions have been reported in an increasing number of chromosomes. Several cases initially interpreted as terminal duplications have instead been documented to represent inverted duplications with terminal deletions. Inv dup del(2p) has been reported in patients who manifest the clinical findings of trisomy 2p syndrome. Here we report on a 2-month-old girl with inv dup del(2p) and clinical manifestations that overlap those found commonly in partial 2p trisomy, as previously reported in the literature. Her clinical picture helps delineate the phenotype of 2p duplication disorders.