Clinical and hematologic aspects of the X‐linked α‐thalassemia/mental retardation syndrome (ATR‐X)

Abstract

The hallmarks of the X-linked alpha-thalassemia/mental retardation (ATR-X) syndrome are severe psychomotor retardation, minor facial anomalies, genital abnormalities, and an unusual form of alpha-thalassemia. The demonstration of HbH inclusions in red blood cells after incubation with brilliant cresyl blue confirms the diagnosis. We describe 15 previously unreported cases and analyse the phenotypic and hematologic findings in these subjects and compare them with previously published cases. This study demonstrates the consistency of the main characteristics of this syndrome and extends the phenotype. Developmental changes in phenotype, in particular the coarsening of the facial appearance, are illustrated. The hematologic findings are shown to vary widely; in some cases the manifestation of alpha-thalassemia may be subtle and missed without repeated examination.

A japanese patient with X-linked α-thalassemia/mental retardation syndrome: An additional case report

“…All the families are of Caucasian origin (Lefort et al, 1993;Gibbons et aL, 1995b). Our present case is the second in Oriental origin next to our previous report (Kurosawa et aL, 1996).…”

“…With single-strand conformation polymorphism analysis on cDNAs from 24 ATR-X patients, muta- Table 1. Clinical findings in our present case, compared to those from the literatures (Lefort et aL, 1993;Gibbons et aL, 1995b;Kurosawa et aL, 1996 Vol. 41, No.…”

“…XH2, the gene for the disorder, mapped to Xql3, was recently identified (Gibbons et al, 1995a). To date there have been 50 published cases from 28 unrelated families in Caucasian origin and from clinical observations a well-defined phenotype has emerged (Lefort et aL, 1993;Gibbons et aL, 1995b). Here we report an additional patient with the ATR-X in Oriental origin next to our previous report (Kurosawa et aL, 1996).…”

“…The demonstration of HbH inclusions in red blood cells after incubation with 1% brilliant cresyl blue confirms the diagnosis. The proportion of cells with HbH inclusions also varies widely from 0.01% to 12.2% (Gibbons et al, 1995b). In the case of high index of suspicion from the family history and phenotype, a careful search for HbH inclusions should be made and repeated.…”

Germline and gonosomal mosaicism in the ATR-X syndrome

“…1 In this X-linked recessive disorder, the biological fitness in affected individuals is zero and, as expected, new mutations are frequently encountered in affected families. Therefore, when counselling the parents of sporadic cases and assessing the risk of recurrence, the ability to identify female carriers is of great importance.…”