Genetic testing: how to check for 5AR2 mutation | Blood testing: how to check for 5AR2 deficiency


Extract from this study that describes step by step how to check for 5AR2 mutation at the genetic level, should you wish to pursue such testing (ie, use it to convince docs it is possible).

Steroid 5a -reductase type-2 Gene Mutations in the Turkish Population


… “Plasma testosterone levels are elevated
and DHT levels are decreased in 5a-reductase
deficiency. Plasma T/DHT ratio is elevated”

… “Measurements of T and
DHT in serum after hCG stimulation, with determination
of T/DHT ratios are required to establish
the diagnosis
. Assessment of urinary excretion of
5a/5b-steroid metabolites as well as measurement
of 5a-reductase enzyme activity in cultured genital
skin fibroblasts are ancillary investigations
. All of
these parameters are highly variable in prepubertal
children and interpretation may be difficult. Therefore,
it is crucial to perform molecular genetic
analysis as an additional means for an accurate


  1. "…[b]screening of each exon for the etiologic mutation
    was performed by SSCP analysis /b. This method
    was first described by Orita and coworkers in 1989
    and is based on the principle of identical electrophoretic
    mobility of identical single stranded DNA
    molecules (19).

The wild type and mutant DNA
are not identical; therefore they have different
mobility on a gel. SSCP technique has sensitivity
close to 100% if stringent conditions are used
. This
feature permits accurate identification of normal,
homozygous and heterozygous individuals
. The
drawback of this method is the requirement of
radioactive nucleotides (a-32P dATP) during the
experiment with its problems of availability and
high cost.

  1. Hiort and coworkers successfully used
    denaturing gradient gel electrophoresis (DGGE) to
    screen for mutations
    (10). This method requires no
    radioactivity. Experience in molecular genetics is
    needed to accurately perform DGGE

When SSCP or DGGE finds an abnormal exon, the mutation
should be characterized by DNA sequencing

  1. An alternative approach is the sequencing of the whole
    gene without employing screening
    . This is a more
    costly way to detect mutations.

Above mentioned methods are used for searching unknown mutations.

  1. If the causative mutation is already known, restriction
    length fragment polymorphisms (RLFP), an easier
    and faster method can be utilized to identify
    patients, carriers and normals

  2. The last step of the molecular genetic approach is the
    determination of the functional significance of the mutation.
    This is achieved by site-directed mutagenesis and invitro
    transfection analysis

Mechanisms that adversely
alter the enzyme function must be delineated prior
to genetic counseling or prenatal diagnosis. Localization
or type of mutation may be responsible for severity
of enzyme dysfunction

A structural change within
the enzyme results in a major dysfunction, as
evidenced by the severe phenotypic abnormalities
and elevated T/DHT ratio found in 5a-reductase
deficient male pseudohermaphrodites


Steroid 5 alpha-reductase 2 deficiency

Selected bits:

Endocrinology: The characteristic endocrine features of 5a-reductase 2 deficiency are as follows:

  1. normal male to high levels of plasma testosterone and low levels of plasma dihydrotestosterone

  2. elevation in the ratio of the concentration of plasma testosterone to dihydrotestosterone in adulthood and after stimulation with hCG in childhood

  3. elevated ratios of urinary 5-beta to 5-alpha metabolites of androgen

  4. diminished conversion of testosterone to dihydrotestosterone in tissues of affected subjects

  5. elevated ratios of urinary 5-beta to 5-alpha metabolites of C21 steroids

  6. markedly increased ratios of plasma testosterone to dihydrotestosterone after the administration of testosterone

Levels of plasma LH are either normal or slightly elevated

"…Defects in testosterone biosynthesis are usually associated with low plasma testosterone levels, but in men with partial enzyme deficiency, testosterone can be normal at the expense of high plasma LH values

The most common hereditary defect in testosterone biosynthesis, 17b-hydroxysteroid oxidoreductase deficiency, can be recognized on the basis of elevated androstenedione levels, and androstenedione should be measured routinely in suspected cases of 5a-reductase deficiency.

The recognition of partial defects in the androgen receptor can be more perplexing, since such defects can impair the development of tissues that are major sites of dihydrotestosterone biosynthesis and hence could cause secondary 5a-reductase deficiency with abnormally high ratios of plasma testosterone to dihydrotestosterone (90, 91)."

"… In our laboratory, [b]characterization of 5a-reductase activity at pH 5.5 in extracts of fibroblasts cultured from the genital skin of patients is a useful means of confirming the diagnosis particularly when parallel measurements exclude the likelihood of an androgen receptor defect /b. "


  1. The ideal agent would be one that replaces the missing dihydrotestosterone; in experimental studies the administration of [b]dihydrotestosterone enanthate by injection at 4- to 6-week intervals results in a sustained elevation of plasma dihydrotestosterone levels /b, but the agent is not available for general use.

  2. A second technique has been to administer testosterone esters in quantities sufficient to elevate plasma testosterone to supraphysiological levels; when this has been done in patients with 5a-reductase deficiency, it is possible to bring dihydrotestosterone levels to the normal male range and to promote virilization in a satisfactory manner (50). Unfortunately, it is not known whether the supraphysiological levels of testosterone are safe over the long term.

  3. A third approach is to administer androgen in a form that does not require 5a-reductase to be active. For example, [b]19-nortestosterone is active in the absence of 5a reduction /b and can be given by injection in an esterified form such as nandrolone decanoate.

  4. A fourth approach is the a[b]dministration of a dihydrotestosterone cream by inunction /b; [b]this regimen raises plasma dihydrotestosterone levels and has resulted in considerable phallic growth in affected infants /b. Although topical androgen administration appears to be safe over the short term, the long-term efficacy and safety have not been established (95).


Here is a lab that does Steroid 5-Alpha-Reductase Deficiency testing – located in SWEDEN. … how_flag=c


Go do it :exclamation:


sorry guys, but reading the study above i don’t understand a nodal-point:
if someone of us has a normal/high level of dht, does it means that we are sure (reasonably) that the 5AR is working fine? or can dht be high also in case of 5AR mutation?



Read through postings in this thread for details… it would appear Adiol-G tests would reveal more insight as to wether 5AR2 is working correctly, since normal DHT may be seen in 5AR2 deficient males (5AR1 provides DHT as well).


thanks mew, i didn’t see that topic. my mistake!


So let me get this right?..If DHT is high and 5AR2 is sufficient,then theoretically one should not have any issues? or does 5AR1 play a huge functional role and is there a reliable test?

Is the Adiol-G a blood test or is it via skin fibroblasts?

I’m assuming that synthetic dht injected or methylated(proviron) or andractim(topical) if elevated is not the only piece of the puzzle,but that the 5AR enzymes themselves play a large role in libido,penis function and brain function?

I would assume that it’s the whole concert of precursor’s hormones,enzymes and metabolites like dht that give quality of errections?

Just like some can take TRT with high dht but if LH and FSH are not being produced from the pituitary and then the testosterone produced from the leydig cells are not using 5AR to make dht then errections might still be lacking.

Therefore you just cant synthetically replace hormones seperately without using enzymes and the brain to aid in formation .I dont think it’s like insulin or thyroid where they’re identical in structure and give you the same effect?

Libido and errections have to work from a-z by using arousal centres>hypothalamus(LHRH)>Pituitary(LH and FSH)>Testosterone from Leydig cells>5AR 1&2 to natty DHT, which brings me back to the Q… Do the enzymes themselves play a critical role in errections,libido and cognitive functioning without having anything to do with conversion of T to DHT? If so it’s a huge problem for most because if the enzymes have been irreversibly damaged and they exist in arousal centres and in the penis,then functioning may never be the same,unless as explained previously one can replace synthetically.

Is there testing for 5AR1 as well?

Testing for 5AR 1 and 2 might be useless,as it will show only amounts and not functionality in important regions. It’s like how many athletes sustain 3 or more moderate concussions that show up as normal on an MRI yet do a neuropshychiatric evaluation or visual evoked potential and it’s frightening to see the amount of functional damage and deficits.

This is only a theory,as I’d like more support.I hope it’s not true and that there is an easy solution.I pray every day for years that we can fix to pre finasteride levels! I am willing to do anything to help myself and others out,as I haven’t been able to provide and enjoy a sexual relationship with a girl I have been attracted to for 10 yrs! Sad but true :cry:

#9 … #PPA659,M1


In addition to the above info, it would appear the most reliable way to get an accurate reading of 5AR2/DHT activity post-Finasteride would be via genital skin fibroblast culture, based on the attached screenshot.




Attached – a recent 2009 paper on testing for 5AR2 deficiency via measuring 5A/5B metabolites & ratios via 24 Urine Panel (ie, Rhein Labs – )

… and gene mutations (ie … how_flag=c )

Print this out… bring to docs. Discussion section sums it all up nicely.
Diagnosis of 5alpha-reductase 2 deficiency.pdf (358 KB)


Our problem isn’t about a deficiency in 5AR type II. If it was, it would be characterised by deficiency in DHT, which it isn’t.

We need some clarity of thought. We can’t just keep circling back over the same ground again and again.



Great find. This is relatively affordable and could help with further answers, although it is a blood test and not genital fibroblast culture in 5AR2-specific tissues where we inhibited 5AR/DHT… still, may provide some insights.


Has anyone had these test performed and if so what where the results?



Maybe we should get just one volunteer and everyone would donate for him: for example 140 PFS sufferers X $5 = $700 :mrgreen:


I would donate! Sady I´m not from the USA. but i try to find Some one, who can make this test in the EU.

What about a normal DHT that is made by 5AR1? IF, Finasterid switches off the gen vor 5AR2 why do most have a flare up and than a crash?? I worked some time in a Uroglogical and we used this effect as a cancer therapie. But it´s normaly not irreversible…it take nearly 6 Month or longer until ppl are normal again. It´s more a rezeptor problem. What we know is… if there are androgens…more AR will made…if there are less Androgens there are less AR…and we only know one kind of AR.


Ganz Immun AG
Hans-Böckler-Straße 109
D-55128 Mainz
Telefon: +49-06131-7205-0
Telefax: +49-06131-7205-100

The lab in Germany makes a moleculargenetik bloodtest for 5AR for 100 EUR.


ı wıll call thıs doctor soon who wrote thıs artıcle and hopefully ı wıll go to see hım.