(A) Genomic architecture and patterns of human inheritance of 45S ribosomal DNA gene clusters. Four families, “ARDO,” “PYFI,” “VAGR,” and “THAE” are shown. Relationship codes: (01) daughter, (02) son, (10) mother, (20) father, (40) maternal grandmother, (60) paternal grandmother, (70) paternal grandfather. Siblings of the same sex and generation are additionally designated “A,” “B” in descending birth order. (Dotted ovals) Bands not represented in either parent. (Square brackets) Bands of nonstoichiometric signal intensity. Cluster lengths are calibrated on chromosomal size standards from S. pombe, H. wingei, and S. cerevisiae and lambda phage concatemers. (B) High resolution. Note resolution of two bands at 600–700 kb in VAGR-02A with respect to the unresolved doublet in this size range in panel A.
