Abstract
Here, we present two thalassemic patients (one male and one female), having unusual
clinical phenotypes. Both had mental retardation in which one was associated with
microcephaly and other had congenital cataract. They were referred to our institute
for clinical evaluation and cytogenetic testing. Both patients were tested for presence
of abnormal hemoglobin by high performance liquid chromatography and found to be thalassemic.
Their β-globin mutation was also determined by amplification refractory mutation system-polymerase
chain reaction. The male patient was found to have intervening sequence 1-5 (G-C)/+,
indicating β-thalassemia trait and the female was found to have Cod 26 (G-A)/IVS 1-5
(G-C), indicating hemoglobin E-β thalassemia. Their cytogenetic analysis of blood
lymphocytes were studied with high-resolution GTG-banding analysis by using chromosome
profiling (Cyto-vision software 3.6) on their chromosomes. Results revealed 46,XY,del(1)(p36.21)
in the male and 46,XX,del(1)(p36.3) in the female. Their genotype variation showed
(based on genome browser) significant gene loss which probably leads to marked phenotype
variation. We believe, thalassemia with mental retardation associated with microcephaly
and congenital cataract, both having loss in chromosome 1, p36 position, is reported
probably first time from India. This report will definitely enlighten all concerns
and add to the information in growing literature.
Keywords
HPLC - ARMS-PCR - cytogenetics - microdeletion
