A BstE II RFLP at the DXS153 locus.

Source/Description: cpX12 is a 1.1 kb EcoRI single-copy genomic fragment cloned into pAT153 from a pool of 100 cosmids isolated from a human/hamster somatic cell hybrid containing only the human X chromosome (1). Polymorphism: cpX12 reveals a two-allele restriction fragment length polymorphism with bands at 0.7 kb and 1.9 kb (Al) or 2.6 kb (A2) after Southern blot analysis of human genomic DNA digested with Rsal. Frequency: Estimated from 56 unrelated CEPH parents (97 X chromosomes total). Al (0.7 + 1.9 kb) = 0.22 A2 (2.6 kb) = 0.78 Of 39 females tested, 14 were heterozygous. XmnI in a screen of six unrelated females. Chromosome Localization: Mapped to Xql2 by Southern blot hybridization to a panel of human/rodent somatic cell hybrids (2, 3). Mendelian Inheritance: X-linked inheritance demonstrated in 14 informative two-and three generation CEPH families. Source/Description: cX37.1 is a 3.3 kb EcoRI single-copy genomic fragment cloned into pAT153 from a cosmid isolated from a human/hamster somatic cell hybrid containing only the human X chromosome (1). Polymorphism: cX37.1 reveals a two-allele restriction fragment length polymorphism with bands at 3.2 kb (Al) and 5.0 kb (A2) after Southern blot analysis of human genomic DNA digested with BstE II. Frequency: Estimated from 57 unrelated CEPH parents (97 X chromosomes total). Al (3.2 kb) = 0.22 A2 (5.0 kb) = 0.78 Of 40 females tested, 15 were heterozygous. Xbal in a screen of six unrelated females. Chromosome Localization: Mapped to Xql2 by Southern blot hybridization to a panel of human/rodent somatic cell hybrids (2, 3). Mendelian Inheritance: X-linked inheritance demonstrated in 15 informative two-and three generation CEPH families. Other Comments: Rare Bglll variant also found with alleles at 5.3 kb (1 of 77 X chromosomes) and ~ 17 kb (76 of 77 X chromosomes). Final filter washes in 0.1xSSC/0.1% SDS at 68°C.