Fanconi anemia (FA) is a rare autosomal recessive genetic disease, associated 
with congenital anomalies and a predisposition to cancers. FA patients exhibit 
spontaneous chromosome breakage and FA cells are sensitive to DNA interstrand 
crosslink agents and expresses high frequency of chromosome breakage. Recently 
13 genes have been shown to be involved with the FA phenotype. We have carried 
out a detailed study in clinically diagnosed FA patients in an Indian 
population. Thirty three patients were clinically diagnosed with FA and had 
aplastic anemia and bleeding abnormalities. The genetic analysis revealed a 
significantly (P<0.0001) high frequency (36.4%) of parental consanguinity in FA 
patients compared to controls (3.33%). Chromosomal analysis revealed spontaneous 
chromosome breakage in 63.64% FA patients. The mitomycin C and diepoxybutane 
induced cultures showed a significantly (P<0.001) high frequency of chromosome 
breakage and radial formation compared to controls. Among 33 patients, nine 
(27.27%) patients developed malignancies and chromosomal abnormalities were 
detected in five (55.5%) patients bone marrow cells including monosomy 5 and 7, 
trisomy 10, der(1q) and inv(7). Cytogenetic investigation is important in 
aplastic anemia to rule out FA. The clinical presentation and the associated 
high frequency of consanguinity in FA, and the molecular analysis are 
complementary in the study of an Indian population.