Genetic testing

APOE ɛ4 Allele Testing and Risk of Alzheimer Disease

Carly Hughes — Sat, 16 Jan 2021 19:31:55 +0000

Date Added:

January 16, 2021

Journal/Publication:

Journal of the American Medical Association

Publisher:

Journal of the American Medical Association

Publication Date:

January 14, 2021

URL:

APOE ɛ4 Allele Testing and Risk of Alzheimer Disease

Type:

Clinical Decision Aids

Format:

Article

DOI (1):

doi:10.1001/jama.2020.15085

Keywords

MeSH

A brief review of the interpretation of APOE tests for diagnosing and predicting dementia of the Alzheimer’s type. James W. Mold, MD, MPH

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A 64-year-old man presented with concern about an abnormal genetic test result for apolipoprotein E (APOE) obtained through his primary care physician. He reported forgetfulness and word-finding difficulties for 3 years but performed all activities of daily living independently and was generally healthy. His father and maternal great aunt developed dementia in their 70s. Physical (including neurologic) examination, basic laboratory studies, and brain magnetic resonance imaging results were normal. The Short Test of Mental Status (STMS) score was 33 (maximal attainable score of 38 indicates best performance). Neuropsychological assessment showed average to above-average performance in all cognitive domains, accounting for age and education. Results of his genetic testing for APOE were reported as follows: “This individual possesses an apolipoprotein E genotype (3 and 4) that indicates, with high specificity, that Alzheimer’s disease is the cause of or a contributor to the observed dementia.

Author/s:

Choudhury, Parichita, Boeve, Bradley F., Ramanan, Vijay K

Consistency of Direct to Consumer Genetic Testing Results Among Identical Twins

Brian Desmarais — Wed, 19 Jun 2019 00:34:45 +0000

Date Added:

June 18, 2019

Journal/Publication:

The American Journal of Medicine

Publication Date:

June 15, 2019

URL:

Consistency of Direct to Consumer Genetic Testing Results Among Identical Twins

Type:

Clinical Research Results

Format:

Article

DOI (1):

10.1016/j.amjmed.2019.04.052

Keywords

MeSH

Direct-To-Consumer Screening and Testing

This study calls into question the accuracy of direct-to-consumer genetic testing. James W. Mold, MD, MPH

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Abstract

Purpose

To evaluate the consistency of 3 commonly used direct to consumer genetic testing kits.

Background

Genetic testing kits are widely marketed by several companies but the consistency of their results is unclear. Since identical twins share the same DNA, their genetic testing results should provide insight into test consistency.

Methods

42 identical twins (21 pairs) provided samples for three testing companies. Outcomes were concordance of ancestry results when i) twin pairs were tested by the same company and ii) the same participant was tested by different companies. Concordance of 8 self-reported traits with 23andMe genetic analyses were also examined.

Results

Concordance of ancestry results when twin pairs were tested by the same company was high, with mean percent agreement ranging from 94.5%–99.2%. Concordance of ancestry results when participants were tested by two different companies was lower, with mean percent agreement ranging from 52.7%–84.1%. Concordance of trait results was variable, ranging from 34.1% for deep sleep and detached earlobes to 90.2% for cleft chin.

Conclusion

The consistency of consumer genetic testing is high for ancestry results within companies but lower and more variable for ancestry results across companies and for specific traits. These results raise questions about the usefulness of such testing.

Author/s:

Huml, A.M., Sullivan C., Figueroa, M., Scott, K., Sehgal, A.R.

Cautions Regarding Over-The-Counter Genetic Tests

Jeffrey Wilson — Sun, 24 Feb 2019 19:45:16 +0000

Date Added:

February 24, 2019

Publication Date:

February 21, 2019

Type:

Patient Education Materials

Format:

Article

Keywords

DNA Tests

Genetic testing

MeSH

DNA

Information for patients about risks involved in getting over-the-counter proprietary DNA testing.

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Over-the-Counter DNA tests are now easy and affordable. They can be informative and fun. However, there are certain risks involved.

Author/s:

Mold, James