Foundations of Genetic Testing

Explore how dna and genes determine traits and inheritance by tracing chromosomes, dna structure, transcription, translation, and the role of coding and noncoding regions, exons, introns, and regulatory elements.

Explain how inheritance transfers genetic information from parent to child, covering meiosis vs mitosis, haploid gametes, paternal and maternal inheritance, de novo variants, and autosomal dominant, recessive, and X-linked patterns.

Explore the two broad categories of genetic testing—cytogenetic and molecular genetic testing—and learn tests like karyotyping, FISH, CMA, exon array, MLPA, WES, and WGS.

Explore cytogenetic testing types, from karyotyping and FISH to CMA and exon arrays, and their resolution in detecting chromosomal changes, CNVs, and exon-level variants.

Explore molecular genetic testing, including targeted testing, gene panels, exome and genome sequencing, mlpa, and southern blot, and compare their resolution and scope from karyotyping to sequencing.

Understand the shift from Sanger to next generation sequencing, compare methods, and outline the main steps of the NGS workflow, including short-read and long-read sequencing.

Compare Sanger and next-generation sequencing, contrasting Sanger's low-throughput single-strand reads with NGS's massively parallel reads, adapters, and no primer design or allele dropout, faster and cheaper.

Explore the genome's structure, from the central dogma to exons and introns, and learn how genome composition guides the choice of dna sequencing methods.

Compare panel, exome, and whole genome sequencing by how much of the genome is analyzed, noting pros, cons, costs, and interpretation needs.

Outline the NGS workflow from DNA extraction and fragmentation to adapter ligation, library enrichment, capture, and PCR amplification, then sequencing and demultiplexing concepts, noting WGS differences.

Explore how Illumina flow cells use bridge amplification to form dense clusters for sequencing by synthesis, then compare short-read limits with long reads from Oxford Nanopore and PacBio.

Decide when genetic testing makes sense by comparing direct-to-consumer and clinical tests, and by considering germline versus somatic variants in cancer to guide test choice for rare single-gene diseases.

Contrast direct-to-consumer and clinical genetic tests, noting DTCs assess traits and ancestry for lifestyle use, while clinical tests diagnose or prognose disease via pathogenic variants in Mendelian or cancer contexts.

Distinguish germline and somatic variants in cancer using NGS by comparing allele frequencies, with germline at 50%–100% and somatic at 1–20%, guiding distinct test design, read depth requirements, and interpretation.

Choose the right genetic test by aligning patient presentation with a single-gene test, targeted panel, exome sequencing, or genome sequencing for germline mendelian disease.

Explore genetic variants and learn how to classify them by inheritance, allele types, and concepts like germline, somatic, mosaic, rare and common variants.

Classify variants by genotype into SNVs, CNVs, SVs, small indels, and repeat expansions, including frameshift and in-frame effects, then assess pathogenicity as pathogenic, benign, or VUS.

Learn the structure of genetic reports, including patient and clinical information, result summaries, and interpretations, and explore how genetic test report types guide next steps using ACMG criteria.

Identify the three genetic test report types: positive, negative, and inconclusive, and learn how report sections, clinical correlation, segregation analysis, and reanalysis guide diagnosis and care.