Evidence-Based Supplement & Herb Guides

Targeted Variant Test: Known Mutation, Family Testing, and Results

Targeted variant testing checks relatives for a known family mutation. Learn who should test, what positive and true-negative results mean, and how to follow up.

A targeted variant test answers a narrow genetic question: is a specific, already identified DNA change present in this person? It is commonly used...

Variant Classification in Genetic Testing: Pathogenic, Benign, VUS, and Results

Genetic variant classification labels findings as pathogenic, likely pathogenic, VUS, likely benign, or benign. Learn the evidence behind each category and reclassification.

Variant classification is the process laboratories use to decide whether a DNA change is likely to cause disease. Most clinical germline reports use five...

Whole-Exome Sequencing (WES) Method: Coding DNA, Variants, and Results

Whole-exome sequencing examines most coding DNA for rare disease variants. Learn how WES works, what trio results mean, what it can miss, and when reanalysis helps.

Whole-exome sequencing, or WES, examines most of the protein-coding regions of thousands of genes at once. These regions, called exons, make up only a...

Whole-Genome Sequencing (WGS) Method: DNA Variants, Structural Changes, and Results

Whole-genome sequencing detects coding, noncoding, copy-number, and structural DNA variants. Learn how WGS works, what results mean, its blind spots, and reanalysis.

Whole-genome sequencing, or WGS, reads DNA across coding and noncoding regions instead of capturing mainly exons. A clinical genome can be analyzed for single-base...

Achondroplasia Genetic Test: FGFR3 Gene Mutation and Results

Understand the achondroplasia FGFR3 genetic test, including common p.Gly380Arg variants, result meanings, inheritance risks, testing methods, and follow-up.

An achondroplasia genetic test looks for a disease-causing change in the FGFR3 gene, usually the specific variant that replaces glycine with arginine at position...

Alpha-1 Antitrypsin Deficiency Genetic Test: SERPINA1 Gene, Liver, Lung, and Results

Learn how SERPINA1 genetic testing confirms alpha-1 antitrypsin deficiency, explains MM, MZ, SZ, and ZZ results, and guides lung, liver, and family follow-up.

An alpha-1 antitrypsin deficiency genetic test identifies inherited variants in the SERPINA1 gene that can lower the amount or function of alpha-1 antitrypsin, often...

Alpha-Thalassemia Genetic Test: HBA1, HBA2 Deletions, Carrier Risk, and Results

Understand alpha-thalassemia HBA1 and HBA2 testing, including deletions, cis and trans carrier results, hemoglobin H disease, partner risk, and pregnancy follow-up.

An alpha-thalassemia genetic test looks for deletions and other disease-causing changes involving the HBA1 and HBA2 genes, which make alpha-globin chains used in hemoglobin....

Alport Syndrome Genetic Test: COL4A3, COL4A4, COL4A5, and Results

Learn how COL4A3, COL4A4, and COL4A5 testing diagnoses Alport syndrome, distinguishes inheritance patterns, explains VUS and negative results, and guides kidney and family care.

An Alport syndrome genetic test examines COL4A3, COL4A4, and COL4A5, the genes that encode part of the type IV collagen network in the kidney’s...

Ashkenazi Jewish Genetic Carrier Screening Panel: Common Conditions and Results

Understand Ashkenazi Jewish carrier screening panels, common conditions, founder versus expanded testing, carrier results, residual risk, partner testing, and reproductive options.

An Ashkenazi Jewish genetic carrier screening panel checks for inherited variants that are more common among people with Ashkenazi Jewish ancestry and can cause...

Autosomal Recessive Carrier Screening Test: Partner Risk and Results

Learn how autosomal recessive carrier screening results combine with partner testing to define couple risk, residual risk, and reproductive options.

Autosomal recessive carrier screening looks for disease-causing gene variants that usually do not make a carrier ill but can create a reproductive risk when...

Becker Muscular Dystrophy Genetic Test: DMD Gene Mutations and Results

Understand how DMD gene testing confirms Becker muscular dystrophy, detects deletions and sequence variants, predicts phenotype, and guides family care.

A Becker muscular dystrophy genetic test examines the DMD gene for variants that reduce the amount or function of dystrophin, a protein that protects...

Beta-Thalassemia Genetic Test: HBB Gene Mutations, Carrier Risk, and Results

Learn how HBB genetic testing diagnoses beta-thalassemia, identifies carriers, clarifies partner risk, and explains positive, negative, and uncertain results.

A beta-thalassemia genetic test examines the HBB gene for variants that reduce or stop production of beta-globin, one of the protein chains in adult...

Biotinidase Deficiency Genetic Test: BTD Gene Mutations and Results

Learn how BTD genetic testing and enzyme activity confirm profound or partial biotinidase deficiency, explain variants, and guide treatment and family risk.

A biotinidase deficiency genetic test analyzes the BTD gene for variants that impair recycling of biotin, a vitamin needed by several metabolic enzymes. Testing...

Canavan Disease Carrier Test: ASPA Gene, Carrier Risk, and Results

Learn how ASPA carrier testing identifies Canavan disease risk, compares founder panels with full-gene testing, and guides partner and pregnancy decisions.

A Canavan disease carrier test looks for pathogenic variants in ASPA, the gene that makes the enzyme aspartoacylase. A person with one disease-causing ASPA...

Congenital Adrenal Hyperplasia Genetic Test: CYP21A2 Gene and Results

Understand how CYP21A2 testing confirms 21-hydroxylase-deficient CAH, resolves pseudogene and deletion complexity, and explains disease and carrier results.

A congenital adrenal hyperplasia genetic test commonly analyzes CYP21A2, the gene responsible for 21-hydroxylase deficiency, which causes the great majority of CAH. Testing can...

Cystic Fibrosis Carrier Test: CFTR Gene Mutations, Risk, and Results

Learn how CFTR carrier testing identifies cystic fibrosis risk, compares panels with sequencing, explains complex variants, and guides partner testing.

A cystic fibrosis carrier test looks for disease-associated variants in CFTR, the gene that controls chloride and bicarbonate transport across epithelial cells. Most people...

Duchenne Muscular Dystrophy Genetic Test: DMD Gene Mutations and Results

Learn how DMD gene testing diagnoses Duchenne muscular dystrophy, detects deletions and sequence variants, explains results, and guides family care.

A Duchenne muscular dystrophy genetic test analyzes the DMD gene to identify the molecular cause of progressive muscle weakness and dystrophin loss. A confirmed...

Ehlers-Danlos Syndrome Genetic Test: COL5A1, COL5A2, COL3A1, and Results

Understand Ehlers-Danlos genetic testing for COL5A1, COL5A2, and COL3A1, including classic and vascular EDS results, negative panels, VUS findings, family risk, and next steps.

An Ehlers-Danlos syndrome genetic test can confirm certain inherited connective tissue disorders, but it is not a single yes-or-no test for every form of...

Expanded Carrier Screening Test: Genetic Disease Risk, Genes, and Results

Learn how expanded carrier screening evaluates genetic disease risk, how panel genes and methods differ, what positive and negative results mean, and how partner findings guide pregnancy options.

Expanded carrier screening checks many genes at once to identify reproductive risks that may not be suggested by ancestry or family history. Most people...

Fabry Disease Genetic Test: GLA Gene Mutations, Symptoms, and Results

Understand Fabry disease GLA genetic testing, including classic and late-onset symptoms, enzyme and lyso-Gb3 results, variant interpretation, X-linked family risk, treatment relevance, and next steps.

A Fabry disease genetic test looks for disease-causing variants in the GLA gene, which provides instructions for the lysosomal enzyme alpha-galactosidase A. When this...