IMPORTANCE Breast cancer in women between the ages of 15 and 39 years (adolescents and young adults [AYAs]) constitutes 5% to 6% of all breast cancer cases in the United States. Breast cancer in AYA women has a worse prognosis than in older women. Five-year survival rates are lowest for AYA women, and only a few studies have examined the impact of delay in treatment, race/ethnicity, and other s...

Adult-onset primary torsion dystonia (AOPTD) has an autosomal dominant pattern of inheritance with markedly reduced penetrance; the genetic causes of most forms of AOPTD remain unknown. Endophenotypes, markers of sub-clinical gene carriage, may be of use detecting non-manifesting gene carriers in relatives of AOPTD patients. The aim of this study was to compare the utility of the spatial discri...

Skeletal muscles are readily characterized by their location within the body and by the number and composition of their constituent muscle fibers. Here, we characterize a mutation that causes a severe reduction in the number of fibers comprising the tergal depressor of the trochanter muscle (TDT, or jump muscle), which functions in the escape response of the Drosophila adult. The wild-type TDT ...

Loss or addition of nucleotides at junctions generated by V(D)J recombination significantly expands the antigen-receptor repertoire. Addition of nontemplated (N) nucleotides is carried out by terminal deoxynucleotidyl transferase (TdT), whose only known physiological role is to create diversity at V(D)J junctions during lymphocyte development. Although purified TdT can act at free DNA ends, its...

Thalassaemia is a public health problem in Malaysia. It is known to cause skeletal deformity. The purpose of this study was to compare the skeletal, dentoalveolar, and soft tissue features of Malay transfusion-dependent thalassaemia (TDT) patients with a Malay control group. Lateral cephalometric radiographs of 30 Malay (14 males and 16 females aged 6.4-21.8 years) TDT patients and 60 normal Ma...

The contribution of template-independent nucleotide addition to antigen receptor diversity is unknown. We therefore determined the size of the T cell receptor (TCR)alpha/beta repertoire in mice bearing a null mutation on both alleles of the terminal deoxynucleotidyl transferase (Tdt) gene. We used a method based upon polymerase chain reaction amplification and exhaustive sequencing of various A...

Merkel cell carcinoma (MCC) is an uncommon tumor with indistinct clinical features. The differential diagnosis includes small cell lung carcinoma (SCLC). We characterized the expression of terminal deoxynucleotidyl transferase (TdT) and a panel of immunohistochemical markers in 40 MCC, 30 SCLC, and 6 pulmonary carcinoid tumor (PCT) cases. We used antibodies against TdT, thyroid transcription fa...

V(D)J recombination generates a remarkably diverse repertoire of antigen receptors through the rearrangement of germline DNA. Terminal deoxynucleotidyl transferase (TdT), a polymerase that adds random nucleotides (N regions) to recombination junctions, is a key enzyme contributing to this diversity. The current model is that TdT adds N regions during V(D)J recombination by random collision with...

CD19+CD10+ human B lineage bone marrow cells were separated into cycling or resting cells, which differ in their expression of CD34, VpreB, recombination activating gene (RAG-1), and terminal deoxynucleotidyl transferase (TdT). Polymerase chain reaction analyses developed for DHJH and VkJk, VkJkK(de) and VkK(de) rearrangements with DNA of single cells and a comparison with B lineage cell develo...

The transmission-disequilibrium test (TDT) of Spielman et al. is a family-based linkage-disequilibrium test that offers a powerful way to test for linkage between alleles and phenotypes that is either causal (i.e., the marker locus is the disease/trait allele) or due to linkage disequilibrium. The TDT is equivalent to a randomized experiment and, therefore, is resistant to confounding. When the...