Cytogenetic investigations in couples with repeated miscarriages and malformed children: report of a novel insertion

Abstract

Recurrent miscarriage and the birth of a malformed child continue to be challenging problems for the patient and clinician. Often, cytogenetic studies have an important role in the evaluation of couples with a poor obstetric history. The present study deals with analysis of chromosome abnormalities in 2150 couples from India, and is the largest group ever reported in the literature. The observed incidence of chromosomal rearrangements in these couples was 3.5%. Apart from reciprocal, Robertsonian, inversions, a unique case of chromosome insertion was identified, which is perhaps only the second report in literature. Minor chromosome variants such as inv(9),inv(Y),9qh+, D/G variants were observed in 108 subjects. Cytogenetic studies should be performed for all couples with repeated miscarriages and bad obstetric history, and in cases of detected chromosomal aberration, the patient should be counselled individually according to the type of anomaly.

Chromosomal abnormalities in couples with recurrent spontaneous miscarriage: a 21-year retrospective study, a report of a novel insertion, and a literature review

“…The first couple was reported in India by Rao L et al, who noticed an insertion in women with karyotype 46,XX,ins(12:6)(12;6)(q24.2;q23q25) [41]. The second was reported by Iyer P, who identified an insertion in men with karyotype 46,XY,ins(1;13)(q22;q31q33) [42], and the third was reported by Fuente-Cortés BED, who found an insertion in women with karyotype 46,XX,ins(15;8)(q26;p11p23) [16]. In our study, we identified a new insertion, 46,XX,ins(6)(p24q21q27), in one woman with RSM, and to the best of our knowledge, this is the fourth insertion reported in the literature.…”

Chromosomal polymorphic variants increase aneuploidies in male gametes and embryos

“…In addition to Robertsonian and reciprocal translocations and inversions, there are also polymorphic variants on chromosomes that are considered 'normal' by cytogeneticists because they involve heterochromatic regions and occur in the general population without apparent clinical significance [Borgaonkar 1997]. However, previous studies have reported that the incidence of these variants is higher in infertile patients [Madon et al 2005], couples suffering from recurrent miscarriage [Iyer et al 2007], and in men with poor sperm quality [Nakamura et al 2001;Nagvenkar et al 2005;Collodel et al 2006]. These variants are quantitative/positional modifications of constitutive heterochromatin.…”

Robertsonian Translocation Between Chromosome Number 13 And 14 Associated With Recurrent Pregnancy Loss

“…Often cytogenetic studies have an important role in the evaluation of couples with a poor obstetric history [1] . Repeated pregnancy loss in first trimester is strongly associated with chromosomal abnormality in couples [2], [3] .…”