Multiple congenital anomalies in a man with (X;6) translocation

Abstract

X;autosome translocations in humans, often associated with congenital anomalies or with gonadal dysgenesis syndromes, are informative for the study of X-linked gene expression and of the phenomenon of X chromosome inactivation. When such translocations occur in association with multiple congenital anomaly (MCA) syndromes, the observed phenotypes are not always attributable solely to disruption of specific genes, if X-inactivation spreads onto the translocated autosome, rendering some distal genes inactive. We report on a man with multiple congenital anomalies and a maternally inherited (X;6)(p22.1;p25) translocation. He has abnormalities not described in the Klinefelter or 6p deletion syndromes. His unique findings constitute a recognizable syndrome, which is likely caused by disomy for a region of Xp in conjunction with a partial 6p deletion.

Refined genotype–phenotype correlations in cases of chromosome 6p deletion syndromes

“…YAC 952h4, which localises in 6p25.3, was positive on the respective del (6). However, PAC dJ223B1, which lies distal to the YAC, did not produce a hybridisation signal on del (6). The breakpoint lies between these probes: based on this result, we have refined the cytogenetic diagnosis and positioned the breakpoint in 6p25.2 (Table 3).…”

“…The results showed this distal region was indeed not deleted on del (6). The most proximal probe that did not hybridise on del (6) was PAC dJ133h11, this probe lies in 6p24.3, immediately distal to dJ167k8, that gave a positive signal on del (6) ( Table 3).…”

“…Therefore the breakpoint lies between these two clones within band 6p24. (Right) Mapping the interstitial deletion in Patient 5; PAC118B18(red), mapping in 6p25, hybridised to both chromosome 6 and del (6), and PAC 172H1 (green) hybridised proximal to PAC118B18 within 6p24 on normal chromosome 6p. A green signal derived from PAC 172H1 is also present on del (6), and overlaps with the red signal (PAC118B18) in 6p25, indicating that a significant proportion of the region distal to 6p24 and proximal to 6p25 has been deleted.…”

47,XY,+der(X)t(X;18)(p11.4;p11.22): A Unique Aneuploidy Associated with Klinefelter Syndrome due to an Extra Derivative X Chromosome Inherited Maternally

“…The karyotype was finally revealed as 46,XY,der(19) t(X;19)(q11.1-11.2;p13.3). Other forms of derivative chromosomes involving X and an autosome, such as t(X;9) and t(X;6), may also be found in Klinefelter-like syndrome patients [Dumars et al, 1975;Sivak et al, 1994]. Though these men were not 'standard' KS patients, they share typical features of KS, such as small testes, sparse body hair, severe oligozoospermia or azoospermia.…”

Deleção terminal do braço curto do cromossomo 6 (6p25.3p24.3): uma revisão de literatura e relato de caso de uma criança brasileira

“…Until 2004, there were only 43 cases in the medical literature, excluding anomalies of ring chromosome 6. Of these, only ten cases described interstitial exclusions with the entire segment 6p22, 6p22.2 -p25.2 or 6p24 -p25 [13][14][15][16][17][18][19][20][21][22][23] .…”