A toddler with phylloid-type pigmentary mosaicism and ambiguous genitalia resulting from trisomy 14 induced by a der(Y)t(Y;14)

Abstract

A 1-year-old baby with phylloid-type pigmentary mosaicism, hypotonia, ambiguous genitalia, and a positive screening test for congenital adrenal hyperplasia was referred. Previous sonograph, cytogenetics, and metabolic profile were inconclusive, therefore we performed an additional karyotype and a molecular cytogenetics studies. A mosaic karyotype 45,X/46,X,der(Y)t(Y;14) was characterized in peripheral blood. Congenital adrenal hyperplasia genes were sequenced and the results were negative. The ambiguous genitalia was the result of the special gonosomal mosaicism. The low level of trisomy 14 led to minor physical characteristics and mild mental retardation; also, Turner syndrome features can be expected rather than severe trisomy 14 stigmata.

Full trisomy 14 in one of bichorionic biamniotic twins

“…Full T 14 is an extremely rarely described lethal chromosomopathy associated with developmental malformation disorders, severe dysmorphia, miscarriages, and fetal death due to organic decompensation. To the best of our knowledge, there are no described cases of full T14 in one fetus from dizygotic BCBA twin pregnancy [1,2].…”

Genética molecular en la clínica: una herramienta necesaria para el diagnóstico definitivo en enfermedades raras

“…El primer cariotipo reportó un mosaico 45,X/46,XX, la ecografía un canal vaginal y hernias inguinales bilaterales y una tomografía un testículo derecho en el escroto y un testículo izquierdo faltante. Se realizó una segunda prueba de tamizaje con un resultado negativo, la cuantificación de hormonas esteroideas fue inconclusa y se comenzó el tratamiento con corticoides 4 . A los 6 meses de edad el paciente presentó retraso en el desarrollo global, e hipotonía y dismorfias faciales.…”