RESUMEN
We report the prenatal diagnosis of a 12q22q23.2 de novo interstitial deletion performed by array based comparative genomic hybridization (array CGH) in a fetus with cystic hygroma colli, intrauterine growth retardation, microcephaly and micrognathism. Haploinsufficiency for insuline-like growth factor 1 gene (IGF1), which is mapped in the deleted region, is suggested because of its implication in prenatal and postnatal growth and in neuronal maturation. This case demonstrates the contribution of array CGH in prenatal diagnosis for detecting small unbalanced chromosomal abnormalities in malformed fetuses and, subsequently, for genetic counselling.
Asunto(s)
Anomalías Múltiples/genética , Aberraciones Cromosómicas , Deleción Cromosómica , Cromosomas Humanos Par 12/genética , Anomalías Múltiples/diagnóstico , Anomalías Múltiples/diagnóstico por imagen , Adulto , Secuencia de Bases , Hibridación Genómica Comparativa , Femenino , Feto , Asesoramiento Genético , Haploinsuficiencia , Humanos , Hibridación Fluorescente in Situ , Factor I del Crecimiento Similar a la Insulina/deficiencia , Factor I del Crecimiento Similar a la Insulina/genética , Cariotipificación , Datos de Secuencia Molecular , Embarazo , Diagnóstico Prenatal , Ultrasonografía PrenatalRESUMEN
Cytogenetic studies of the parents of a girl with the DiGeorge (or velocardiofacial) syndrome, who carried a deletion at 22q11.2, revealed an unexpected rearrangement of both 22q11.2 regions in the unaffected father. He carried a 22q11.2 deletion on one copy of chromosome 22 and a reciprocal 22q11.2 duplication on the other copy of chromosome 22. Genetic compensation, which is consistent with the normal phenotype of the father, was shown through quantitative-expression analyses of genes located within the genetic region associated with the DiGeorge syndrome. This finding has implications for genetic counseling and represents a case of genetic compensation in a human genomic disorder.