"Antimongolism" syndrome.

A 45,XX,21--child: attempt at a cytological and clinical interpretation of the karyotype.

“…21 is the only chromosome compatible with life and development in the trisomic state. Furthermore, deficiencies of the chromosomes in group G are of three categories: deletions associated with congenital abnormalities (Weleber, Hecht, and Giblett, 1968;Ricci, Dallapiccola, and Preto, 1970;Warren and Rimoin, 1970), monosomy for one cell line likewise associated with a variation of abnormalities (Lejeune et al, 1964;Reisman et al, 1966;Bauchinger, Schmid, and R6ttinger, 1968;Challacombe and Taylor, 1969;Endo et al, 1969;Zdansky et al, 1969), and, finally, deletions without any clinical signs (Migeon, 1965;Neu, Leao, and Gardner, 1966). In the various cases with abnormalities the clinical picture shows considerable variation.…”

An unusual chromosomal aberration in a case of Chediak-Higashi syndrome.

“…In view of the peculiar downward slant of this patient's eyes, and other findings that were the opposite of those seen in Down's syndrome, the term 'antimongolism' was assigned to this newly discovered entity, and several patients with similar phenotype have since been described (Penrose, 1966;Thorburn and Johnson, 1966;Reisman et al, 1966;Al-Aish et al, 1967;R. C. Hindle, 1969, personal communication to Challacombe andTaylor (1969);Challacombe and Taylor, 1969;Endo et al, 1969). However, there have also been reports of patients whose chromosomes frequently showed incomplete and sometimes complete, inborn monosomy for a G chromosome but without antimongoloid features (Cohen, 1966;Engel et al, 1966;McIlree, Tulloch, and Newsam, 1966;Reisman et al, 1967;Weleber, Hecht, and Giblett, 1968;Blank and Lorber, 1969) (Table II).…”

A child with a ring G chromosome (46,XX, Gr).

“…The occurrence of monosomy or deletion of a group G chromosome has been reported in several patients with mental retardation and multiple abnormalities (Polani, 1969 (German and Bearn, 1962;Thorburn and Johnson, 1966;Hall, Frega, and Svenningsen, 1967;Hindle, 1967;Al-Aish et al, 1967;Endo et al, 1969;Challacombe and Taylor, 1969) suggests that they constitute a definite syndrome. The major features are physical and mental retardation, hypertonia, failure to thrive, and an abnormal facies.…”

“…Several cytogenetic variants of antimongolism have been observed: apparent monosomy G (Thorburn and Johnson, 1966;Hall et al, 1967;Al-Aish et al, 1967); deletion Gq- (German and Bearn, 1962;Reisman et al, 1966;Hindle, 1967); and mosaicism Gq-/G- (Lejeune et al, 1964;Endo et al, 1969;Challacombe and Taylor, 1969). It is possible that among the reported cases of deletion of a G chromosome may have been some in which the true abnormality was a ring chromosome (German and Bearn, 1962;Lejeune et al, 1964;Challacombe and Taylor, 1969).…”