Paternal uniparental disomy of chromosome 14 and unique exchange of chromosome 7 in cases of spontaneous abortion

Abstract

To investigate the involvement of uniparental disomies (UPDs) in spontaneous abortion, the polymorphic patterns of microsatellites on each chromosome were analyzed in 164 cases of abortion. Eighty-three of the 164 cases had chromosomal abnormalities. In 79 of the remaining 81 cases with normal karyotypes, the microsatellite analysis revealed that biparental patterns were present in the informative microsatellites in all chromosomes. In one of the remaining two cases, however, the polymorphic patterns of chromosome 14 appeared to be both of paternal origin. The patterns of the distal of the long arm were homozygous, and those of the remaining region were heterozygous. That is, this fetus had paternal UPD 14, originating from meiosis I nondisjunction. In the other case, the polymorphic patterns of the distal one third of the long arm of chromosome 7 were uniparental (maternal) in origin whereas those of the remaining region of this chromosome were biparental. These findings thus suggested that this chromosome might have originated from chromatid exchange between the long arms of paternal and maternal chromosome 7 at the first mitotic division. Microsatellite analysis, however, produced no evidence of duplication or deletion of any segments. The findings also suggest the possibility that some UPDs may cause spontaneous abortion.

Improved assay performance of single nucleotide polymorphism array over conventional karyotyping in analyzing products of conception

“…However, UPD also causes abnormal embryonic/fetal development or even miscarriage, although the frequency of UPD-associated miscarriage may be low, which was estimated to occur in < 3% of miscarriage cases. 21,22 Several studies found that UPDs, for example, with maternal uniparentalheterodisomy of chromosome 9, 21 paternal UPD of chromosome 14, 22 maternal uniparentalisodisomy and uniparentalheterodisomy of chromosome 16, 23 and paternal uniparentalisodisomy of chromosome 21, 21 could cause miscarriage. Moreover, it was well known that wholegenome UPD was not compatible with life, and paternal origin would lead to complete hydatidiform mole, resulting in embryonic death.…”

Complex and segmental uniparental disomy updated

“…The unavailability of parental DNA questions the results, but both parents were noted as being healthy and the identical mutation event in maternal and paternal meiosis seems highly unlikely. In a study on the relevance of UPD for spontaneous abortions Tsukishiro et al found telomeric maternal isodisomy 7q 106. Genes on 7q are considered to be relevant for autism spectrum disorder; so in a study on 60 pedigrees each with at least one individual affected by autism spectrum disorder, one case of not exactly defined interstitial maternal UPD 7q was identified 108.…”

Prenatal diagnostic indicators of paternal uniparental disomy 14

“…Accumulating evidence is supporting the view that a distinct phenotype is also associated with paternal UPD 14 (pat UPD14). Currently, 13 cases of pat UPD for the entire chromosome 14 and one case of segmental pat UPD 14 have been reported (Table 1) Furthermore, pat UPD14 has recently been found in a human spontaneous abortion (Tsukishiro et al, 2005). Clinical features described in almost all cases include polyhydramnios, small thorax with abnormally curved ribs, dysmorphic facial features and severe postnatal respiratory distress.…”