On the parental origin of the X's in a prenatally diagnosed 49,XXXXX syndrome

Abstract

A 49,XXXXX fetus was detected in amniotic fluid cell cultures from a 39-year-old mother. On ultrasonography, growth retardation and bilateral radioulnar synostosis were found. Additional clinical manifestations were mild facial anomalies and hypoplastic ovaries depleted of oocytes. Molecular analysis showed that this aneuploidy arose by successive maternal non-disjunction.

Pentasomy X and hyper IgE syndrome: co-existence of two distinct genetic disorders

“…In addition, the results of DNA polymorphism analysis support a mechanism of sequential non disjunctions in meiosis I and II in the mother, involving both chromatid pairs in meiosis II. This is in agreement with previously reported cases of X-chromosome tetrasomy or pentasomy of maternal origin [8,9,11,16]. Immunological abnormalities in association with the penta-X syndrome have not been reported so far, except in one patient who had elevated serum IgM levels up to 175 mg/dl, more than six standard deviations above the mean for age [10,20].…”

Rare sex chromosome aneuploidies in humans: Report of six patients with 48,XXYY, 49,XXXXY, and 48,XXXX karyotypes

“…In the present patient the severe chest deformity caused recurrent respiratory infections as well as progressive heart failure resulting in early death. A 49,XXXXY karyotype may result either from a postzygotic nondisjunction in a XXY zygote or from consecutive nondisjunctions in maternal meiosis I and II [Celik et al, 1997;Martini et al, 1993], given that all the X chromosomes are of maternal origin [Villamar et al, 1989]. Parental age is not advanced in most of the reported 49,XXXXY patients, as in the present one.…”

Transient hydrops fetalis in a prenatally diagnosed pentasomy X?

“…Craniofacial anomalies are hypertelorism, epicanthus and mongoloid slant of the palpebral fissures, as seen in Down Syndrome, 7 a flat broad nose, malformed teeth, cleft or high palate, low set ears, a short or webbed neck, a low hair line and micrognathia 4 . Skeletal abnormalities include clinodactyly, overlapping toes, lax joints, radio‐ulnar synostosis, dislocation or subluxation of the joints, a narrow chest, talipes equinovarus and scoliosis 5 . There is also retardation of psychomotor development, delayed speech and difficulty in communication.…”

“…Only three pentasomy X cases in the literature have previously been diagnosed prenatally. The first case had growth restriction and radio‐ulnar synostosis determined on ultrasonographic examination 5 . The second case was diagnosed at 33 weeks' gestation, and had Dandy–Walker malformation, hydrocephaly, a ventricular septal defect, hypertelorism and polyhydramnios 6 .…”