Robertsonian Translocations: An Overview of 872 Robertsonian Translocations Identified in a Diagnostic Laboratory in China

Abstract

Robertsonian translocations (ROBs) have an estimated incidence rate of 1/1000 births, making this type of rearrangement the most common structural chromosomal abnormalities seen in the general population. In this study, we reports 872 cases of ROBs from 205,001 specimens karyotyped postnatally in a single accredited laboratory in China, including 583 balanced ROBs, 264 unbalanced ROBs, 9 mosaic ROBs, and 18 complex ROBs. Ninety-three percent of the balanced ROBs observed were adults with infertility, miscarriage, or offspring(s) with known chromosomal abnormalities. Significant excess of females were found to be carriers of balanced ROBs with an adjusted male/female ratio of 0.77. Ninety-eight percent of the unbalanced ROBs observed were children with variable referral reasons. Almost all of the unbalanced ROBs involved chromosome 21 except a single ROB with [46,XX,der(13;14),+13] identified in a newborn girl with multiple congenital anomalies. Multiple novel ROB karyotypes were reported in this report. This study represents the largest collections of ROBs in Chinese population.

The application of PGT-A for carriers of balanced structural chromosomal rearrangements

“…Robertsonian translocations are one of the most frequent reorganizations in humans. Most of the cases analyzed correspond to rearrangements with chromosomes from the D-group (chromosomes 13, 14 and 15), whereas some rare Robertsonian translocations are scarcely found in the literature, mainly those with both chromosomes from the G-group (chromosomes 21 and 22) and those involving chromosomes from both groups (D;G translocations) [10,12,13].…”

Two Familial Cases of Robertsonian Transloacations 13; 14 and Its Clinical Consequences

“…Recently, a study from Chinese population on 872 cases of Robertsonian translocations revealed 93% of the balanced translocations were having problem of infertility, miscarriage, or offspring(s) with known chromosomal abnormalities [13]. In our study, both the carrier of [rob t (13;14)], i.e., father in case-1 and mother in case-2 ( Figures 1A and 1B) were phenotypically normal (except soft soft sub-mucous cleft palate with father in case-1).…”

Resolving Paradoxes of Robertsonian Translocations

“…Translocations Couple with reproductive disorders (Tables S5, S6) Single cases tested for various reasons (Table S9) Consecutive patients from a genetic unit [44] Total Table 5. Spectrum of homologous translocations and sex ratio among carriers, updated from [43].…”