Does the index-to-ring finger length ratio (2D:4D) differ in amyotrophic lateral sclerosis (ALS)? Results from an international online case-control study.

ABSTRACT:

Objectives

The ratio of the length of the index finger (2D) to the ring finger (4D) (2D:4D) has been reported to be lower (ie, 2D<4D) in people with amyotrophic lateral sclerosis (ALS) than non-ALS controls. This has led to suggestions that exposure to increased prenatal testosterone, which also lowers this ratio, could be a risk factor for ALS. In an attempt to test this hypothesis, we examined 2D:4Ds from large numbers of patients with ALS and controls.

Setting

An online multilingual questionnaire enabling respondents to measure their own index and ring finger lengths.

Participants

Of the initial 949 respondents, 572 remained for analysis after elimination for inability to straighten fingers, not answering the question, statistical outliers and aged <40 years. Respo

SUBMITTER: Parkin Kullmann JA 

PROVIDER: S-EPMC5726056 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature