CCR5 and laryngotracheoesophageal cleft: The main task of our study was to determine the relationship between polymorphic variants of genes TP53c.215 G>C (Arg72Pro), MDM2c.-5+309 G>T, MDM4c.1q32 A>C, MTHFRc.677 C>T, CASP8c.-652 6N ins/del, CCR5-∆32 and LC patients’ survival.