Evidence-Based Supplement & Herb Guides

Neurofibromatosis Type 2 Genetic Test: NF2 Gene Mutations and Results

NF2 genetic testing explained: NF2-related schwannomatosis, mosaic and tumor testing, result interpretation, surveillance, hearing care, and family risk.

An NF2 genetic test looks for disease-causing changes in the NF2 gene, which can predispose a person to vestibular schwannomas, meningiomas, spinal tumors, peripheral...

Niemann-Pick Disease Genetic Test: SMPD1, NPC1, NPC2 Genes, and Results

Learn how SMPD1, NPC1, and NPC2 genetic testing identifies Niemann-Pick disease, what positive, carrier, negative, and uncertain results mean, and which follow-up tests may be needed.

A Niemann-Pick disease genetic test looks for disease-causing variants in SMPD1, NPC1, or NPC2, but these genes do not all cause the same disorder....

Osteogenesis Imperfecta Genetic Test: COL1A1, COL1A2 Genes, and Results

Understand how COL1A1 and COL1A2 genetic testing confirms osteogenesis imperfecta, how positive, negative, and uncertain results are interpreted, and what they mean for family risk and care.

An osteogenesis imperfecta genetic test most often examines COL1A1 and COL1A2, the genes that encode type I collagen. A pathogenic variant in either gene...

Pan-Ethnic Carrier Screening Test: Common Genetic Disorders and Results

Learn how pan-ethnic carrier screening tests common inherited disorders, how positive and negative results affect couple risk, and what partner testing and reproductive options may follow.

Pan-ethnic carrier screening tests people for inherited conditions without limiting the panel to disorders historically associated with one ancestry group. It is usually offered...

Phenylketonuria (PKU) Genetic Test: PAH Gene Mutations and Results

Learn how PAH genetic testing confirms phenylketonuria, how positive, carrier, negative, and uncertain results are interpreted, and why blood phenylalanine still guides treatment.

A phenylketonuria genetic test looks for pathogenic variants in the PAH gene, which provides instructions for phenylalanine hydroxylase. This enzyme converts the amino acid...

Polycystic Kidney Disease Genetic Test: PKD1, PKD2 Genes, and Results

Learn how PKD1 and PKD2 genetic testing confirms ADPKD, explains inheritance, clarifies uncertain results, and guides family testing and kidney follow-up.

A polycystic kidney disease genetic test looks for inherited changes that explain cyst formation, most often in PKD1 or PKD2. It can confirm autosomal...

Pompe Disease Genetic Test: GAA Gene Mutations, Carrier Risk, and Results

Understand GAA genetic testing for Pompe disease, including enzyme confirmation, carrier risk, pseudodeficiency, newborn screening, and positive or uncertain results.

A Pompe disease genetic test analyzes the GAA gene for inherited variants that reduce acid alpha-glucosidase activity. Pompe disease is an autosomal recessive lysosomal...

Primary Ciliary Dyskinesia Genetic Test: Ciliary Gene Mutations and Results

Learn how primary ciliary dyskinesia genetic testing identifies ciliary gene variants, works with nasal nitric oxide and microscopy, and explains family risk.

A primary ciliary dyskinesia genetic test looks for inherited variants that disrupt the structure or movement of motile cilia. These microscopic structures clear mucus...

Retinitis Pigmentosa Genetic Test: Inherited Eye Disease Genes and Results

Understand retinitis pigmentosa genetic testing, inherited retinal disease genes, inheritance patterns, syndromic risks, and positive or uncertain results.

A retinitis pigmentosa genetic test searches for inherited variants that damage retinal photoreceptors or supporting cells. Retinitis pigmentosa (RP) is not one disease caused...

Sickle Cell Genetic Test: HBB Gene, Trait, Disease, and Results

Learn how HBB genetic testing distinguishes sickle cell trait from HbSS, HbSC, and sickle beta-thalassemia and clarifies newborn and family results.

A sickle cell genetic test analyzes the HBB gene, which provides instructions for beta-globin, one part of adult hemoglobin. The classic sickle variant changes...

Spinal Muscular Atrophy (SMA) Carrier Test: SMN1 Gene, Copy Number, and Results

Understand SMA carrier testing, including SMN1 copy number, 2+0 silent carriers, duplication markers, residual risk, partner testing, and prenatal results.

A spinal muscular atrophy carrier test estimates whether a person has a nonworking copy of SMN1, the main gene responsible for 5q spinal muscular...

Standard Carrier Screening Panel: Cystic Fibrosis, SMA, Fragile X, and Results

Understand standard carrier screening for cystic fibrosis, SMA, and Fragile X, including test methods, result categories, residual risk, partner testing, and reproductive follow-up.

A standard carrier screening panel commonly combines tests for cystic fibrosis, spinal muscular atrophy, and Fragile X syndrome. The three conditions are grouped for...

Stargardt Disease Genetic Test: ABCA4 Gene Mutations and Results

Learn how ABCA4 genetic testing confirms Stargardt disease, how to interpret two variants, one variant, VUS, negative results, phase, prognosis, and family risk.

A Stargardt disease genetic test looks for the molecular cause of an inherited macular disorder that can begin in childhood, adolescence, or adulthood. Most...

Tay-Sachs Disease Carrier Test: HEXA Gene, Enzyme, and Results

Understand Tay-Sachs carrier testing with HEXA gene and Hex A enzyme analysis, including pseudodeficiency, B1 variants, pregnancy specimens, results, and partner risk.

Tay-Sachs carrier testing can involve two complementary kinds of evidence: the activity of beta-hexosaminidase A enzyme and analysis of the HEXA gene. Both aim...

Tuberous Sclerosis Genetic Test: TSC1, TSC2 Genes, Risk, and Results

Understand TSC1 and TSC2 genetic testing for tuberous sclerosis, including diagnostic results, VUS, negative tests, mosaicism, inheritance risk, and surveillance.

A tuberous sclerosis genetic test analyzes TSC1 and TSC2 for variants that disrupt regulation of cell growth. A pathogenic or likely pathogenic variant in...

Wilson Disease Genetic Test: ATP7B Gene Mutations, Copper, and Results

Understand Wilson disease ATP7B genetic testing and copper results, including ceruloplasmin, urine and liver copper, two variants, carrier findings, VUS, and family risk.

A Wilson disease genetic test searches ATP7B for variants that impair the body’s ability to move copper into bile and incorporate it normally into...

X-Linked Carrier Screening Test: Female Carrier Risk and Results

Understand X-linked carrier screening, female carrier risk, inheritance for sons and daughters, test methods, result meanings, health follow-up, and pregnancy options.

X-linked carrier screening looks for disease-associated changes in genes located on the X chromosome. It is often discussed as a reproductive test for women,...

Autoimmune Disease Genetic Risk Test: HLA, Immune Genes, and Results

Learn what an autoimmune disease genetic risk test measures, how HLA and immune-gene results are interpreted, and why positive or negative findings do not provide a diagnosis.

An autoimmune disease genetic risk test looks for inherited DNA differences linked to conditions in which the immune system attacks the body’s own tissues....

Common Variable Immunodeficiency (CVID) Genetic Test: Immune Disorder Genes and Results

Learn how CVID genetic testing examines immune-disorder genes, what positive, negative, and uncertain results mean, and when a molecular diagnosis may change care.

A common variable immunodeficiency genetic test searches for inherited or newly occurring DNA variants that can cause a CVID-like immune disorder. It may examine...

Complement Deficiency Genetic Test: Immune System Genes and Results

Learn how complement deficiency genetic testing evaluates immune-system genes, how CH50 and AH50 guide diagnosis, and what positive, negative, or uncertain results mean.

A complement deficiency genetic test looks for DNA variants that reduce, eliminate, or dysregulate proteins in the complement system. Complement is a network of...