Practice question

Balanced translocation carriers possess exchange of chromosome material with no net gain or loss of euchromatin; all genes remain present in diploid dosage, though rearranged. Therefore development proceeds normally without dosage imbalance or haploinsufficiency. Phenotype appears normal because gene expression remains regulated despite altered linkage. Clinical risk emerges during gametogenesis where aberrant segregation of quadrivalent produces unbalanced gametes carrying duplications and deletions, leading to infertility, recurrent abortions, or offspring with congenital anomalies. Karyotyping and FISH identify balanced carriers for genetic counseling.