The Role of the Genetic Counselor - Empowerment Series - 3/14/19
19:18-22:20
So now we'll move on to our next most common rule for genetic counselors. We've already covered this a little bit in the previous case example, but I want to discuss some other important cases that illustrate the importance of selecting the most appropriate test for a patient. Next slide.
では、遺伝子カウンセラーが守るべき、他の一般的なルールについて説明します。これについては症例①でも多少触れましたが、検査対象として最適な遺伝子を選ぶことがいかに重要であるかを示す、他の例をご紹介します。
So in this example, we'll be comparing two children who are referred to us for the exact same reason. They both have aortic root dilation, again that enlargement near at the beginning of the aorta and pectus excavatum or that indentation in the chest wall. Next slide.
この例では、全く同じ理由で当クリニックに紹介された2人の子どもを比較します。2人とも大動脈の拡張と漏斗胸がみられました。
For this case, we have a 10-year-old boy, who in addition to his aortic dilation and pectus, is also extremely tall for his age and has very long fingers and toes. He's also very nearsighted and needs to wear glasses for that.
一人目は10歳男児です。大動脈拡張、漏斗胸の他に、年齢とは不釣り合いに極めて背が高く、手足の指が非常に長く、強度の近視でメガネをかけていました。
So similar to the very first case we talked about, all of these features together start to paint a picture of a connective tissue disorder.
これらの所見により、症例①と同じく結合組織疾患を疑いました。
But before we dive into the recommended genetic testing for him, let's look at our other patient. So this is an 8-year-old little girl who has aortic root dilation but her pectus actually has a different appearance than the boy we just talked about. So in this patient, she has a chest wall that points outwards at the top and then starts to point inwards at the bottom, which gives her sternum a very unique s-shaped appearance.
二人目は、8歳女児です。大動脈拡張はみられましたが、胸の外見が1人目の男児とは違っていました。胸骨が、胸の上部では外側に突き出し、胸の下部では内側に凹み、非常に特徴的なS字型をしていていました。
This little girl is also very short for her age so her height falls below the 10th percentile, meaning she's a lot shorter than other children of the same age and during her physical exam, we also noted that she had a webbed neck or extra skin at the base of her neck and she also has eyes that are very widely spaced in slant downwards.
またこの女児は年齢の割に非常に小さく、10パーセンタイル未満でした。つまり、同年齢の子どもたちよりもはるかに身長が低いということです。また、身体検査では、翼状頚、つまり首の付け根から余分な皮膚が翼のように広がっており、眼の間隔が非常に広く、垂れ目でした。
And when we see all of these features together, this really makes us think that the patient is likely to have a genetic condition but rather than a connective tissue disorder, we actually think she has something else altogether. Next slide.
これらを総合して考えると、この女児は遺伝性疾患の可能性はあるものの、結合組織疾患ではない他の疾患ではないかと考えました。
Despite these patients coming in for the same original reason so that aortic root dilation and the pectus, they will actually have two different genetic tests order.
この2人の子どもは大動脈拡張と胸骨異常という同じ理由で紹介されたのですが、2人とも別の遺伝子検査がオーダーされました。
For the little girl fits a very classic picture of a condition you might not have heard before called Noonan syndrome and this is a genetic disorder that is caused by a completely different set of genes that aren't found on the connective tissue disorder panel at all.
皆さんご存じないとは思いますが、この女児は、ヌーナン症候群という疾患でみられる典型的な臨床像に一致していました。ヌーナン症候群とは、結合組織疾患で検査対象とする遺伝子とは全く異なる遺伝子により発症する遺伝性疾患です。
Because of this, we recommended that she have Noonan syndrome panel test, which includes all the genes known to cause that condition. And for the little boy, we recommended a connective tissue disorder panel because his features were more consistent with that diagnosis. Oops, sorry, animations, press there a couple times to the next one. There we go.
したがって、この女児はヌーナン症候群の原因遺伝子の遺伝子パネル検査を受けることとなり、結合組織疾患に合致する所見のある男児は、結合組織疾患の遺伝子パネル検査を受けました。
So when their genetic testing results came back, the little girl had a mutation in the PTPN11 gene, which causes Noonan syndrome and the little boy had a mutation in his FBN gene, giving him a diagnosis of Marfan syndrome.
遺伝子パネル検査の結果ですが、女児はヌーナン症候群の原因遺伝子であるPTPN11遺伝子の変異が見つかりました。男児はフィブリリン遺伝子の変異が見つかったことで、マルファン症候群の診断が付きました。
So what we've learned from this case is even though they are referred for very similar reasons, had we not ordered the appropriate panel for either one of these patients, we could have missed their true diagnosis.
この例からわかるように、患者さんが紹介された理由が同じであるとしても、それぞれの患者さんに適した遺伝子パネル検査をオーダーしなければ、正しい診断を見逃す可能性があるということです。
The Marfan Foundation did not participate in the translation of these materials and does not in any way endorse them. If you are interested in this topic, please refer to our website, Marfan.org, for materials approved by our Professional Advisory Board.
The Marfan Foundation は、当翻訳には関与しておらず、翻訳内容に関してはいかなる承認も行っておりません。このトピックに興味をお持ちの方は、Marfan.org にアクセスし、当協会の専門家から成る諮問委員会が承認した内容をご参照ください。
